SEARCH · Search PubMed

Results for “maternal genetic variants”

Search indexed PubMed citations on genomics, clinical trials, systematic reviews and public health. Explore titles, authors and supplied subject terms, then open the PubMed record.

SourceResearch connectionFrom yearThrough year

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources

PubMed2026

Maternal genetic variants associated with aneuploid conception: a narrative review.

BACKGROUND: Human aneuploid conception, a leading cause of infertility, pregnancy loss, and congenital disorders (e.g. Down's syndrome), arises from errors in chromosome segregation during oocyte meiosis or embryonic mitosis. While advanced maternal age is a well-established risk factor, significant inter-individual variation exists among younger women, suggesting a substantial role for maternal genetic determinants. OBJECTIVE AND RATIONALE: This review summarizes the identified maternal genetic variants associated with aneuploid conceptions and highlights directions for future research. SEARCH METHODS: We systematically searched PubMed, Embase, and the Cochrane Library (up to 12 January 2026), using key terms related to maternal genetics, genetic variants, aneuploidy, and pregnancy. Inclusion criteria were human studies, genetic confirmation of aneuploidy (in oocytes/embryos/products of conception/fetal cells), maternal variants (rare single-nucleotide variations, single-nucleotide polymorphisms, and small indels [≤50 bp]), and English-language publications. Exclusion criteria were non-human studies, structural/non-aneuploid numerical abnormalities, paternal factors, and conference abstracts. Extracted data items included study identifiers, population characteristics, variant details, detection methods, clinical phenotypes, type and origin of aneuploidy, pathogenicity or effect assessment, and gene inclusion in currently commercially available infertility next-generation sequencing (NGS) panels. Rare variants were classified per American College of Medical Genetics and Genomics and the Association for Molecular Pathology (ACMG/AMP) guidelines, whereas common variants were evaluated based on effect estimates and functional validation. Study quality was appraised using a modified Newcastle-Ottawa Scale. Supplementary searches explored associations between the identified genes and a broader range of reproductive phenotypes. OUTCOMES: From 28 studies covering the broad clinical spectrum of aneuploid pregnancies (including embryo arrest, implantation failure, pregnancy loss, hydatidiform mole, and fetal aneuploidy), we identified maternal variants associated with aneuploid conceptions. These were functionally categorized into meiotic recombination, spindle dynamics, checkpoint enforcement, and the maternal-to-zygotic transition. Among them, variants in several genes are supported by higher-quality evidence, including likely pathogenic rare variants in KIF18A, ELL3, and CEP120, as well as common variants in PLK4 and CCDC66. Although some identified genes (HFM1, MCM9, MEI1, BUB1B, NLRP2, NLRP7, and TLE6) are included in commercial infertility NGS panels, their direct association with aneuploidy requires further validation. WIDER IMPLICATIONS: This review proposes that 'aneuploidy predisposition' constitutes a critical, mechanism-driven dimension for the genetic diagnosis of infertility, complementing phenotype-based frameworks. This approach would best serve women with unexplained infertility and a normal karyotype who have either a history of recurrent aneuploidy or heterogeneous reproductive phenotypes across different cycles. Adopting this perspective refines clinical genetic testing paradigms and underscores the need to prioritize artificial intelligence-enhanced clinico-genomic association studies and develop polygenic risk models integrated with clinical factors. PROSPERO REGISTRATION NUMBER: CRD42025636217.

Humans↗

PubMed2024

Dual diagnosis of achondroplasia and mandibulofacial dysostosis with microcephaly.

BACKGROUND: Achondroplasia and mandibulofacial dysostosis with microcephaly (MFDM) are rare monogenic, dominant disorders, caused by gain-of-function fibroblast growth factor receptor 3 (FGFR3) gene variants and loss-of-function elongation factor Tu GTP binding domain-containing 2 (EFTUD2) gene variants, respectively. The coexistence of two distinct Mendelian disorders in a single individual is uncommon and challenges the traditional paradigm of a single genetic disorder explaining a patient's symptoms, opening new avenues for diagnosis and management. CASE PRESENTATION: We present a case of a female patient initially diagnosed with achondroplasia due to a maternally inherited pathogenic FGFR3 variant. She was referred to our genetic department due to her unusually small head circumference and short stature, which were both significantly below the expected range for achondroplasia. Additional features included distinctive facial characteristics, significant speech delay, conductive hearing loss, and epilepsy. Given the complexity of her phenotype, she was recruited to the DDD (Deciphering Developmental Disorders) study and the 100,000 Genomes project for further investigation. Subsequent identification of a complex EFTUD2 intragenic rearrangement confirmed an additional diagnosis of mandibulofacial dysostosis with microcephaly (MFDM). CONCLUSION: This report presents the first case of a dual molecular diagnosis of achondroplasia and mandibulofacial dysostosis with microcephaly in the same patient. This case underscores the complexity of genetic diagnoses and the potential for coexistence of multiple genetic syndromes in a single patient. This case expands our understanding of the molecular basis of dual Mendelian disorders and highlights the importance of considering the possibility of dual molecular diagnoses in patients with phenotypic features that are not fully accounted for by their primary diagnosis.

Humans↗

PubMed2026

Emerging genes implicated in human congenital heart disease: a 2023-2025 scoping review.

BACKGROUND: Congenital heart disease (CHD) is the most common major congenital anomaly and a leading cause of infant morbidity and mortality. The rapid expansion of genomic technologies has accelerated the discovery of rare genetic variants implicated in CHD pathogenesis. However, most individuals with CHD still lack an identifiable molecular etiology. The purpose of this scoping review is to systematically characterize genes reported in the recent literature as candidate CHD-associated genes and contextualize these findings within the stages of cardiac morphogenesis. METHODS: PubMed was searched using predefined terms related to CHD and genetic variants, supplemented by a prospectively maintained internal database. We included human studies published between January 2023 and December 2025 that identified pathogenic, likely pathogenic, or uncertain monogenic variants in at least one patient with CHD. Animal-only studies, chromosomal abnormalities, copy number variants, multigenic associations, transcriptomic/proteomic analyses, reviews, and maternal-only genetic studies were excluded. Gene-disease validity classifications were assigned using the Clinical Genome Resource (ClinGen) CHD Gene Curation Expert Panel framework. RESULTS: Of 2,834 screened articles, 391 studies met inclusion criteria, identifying 912 unique genes reported as candidate CHD-associated genes. Frequently reported genes included PTPN11, NOTCH1, GATA4, JAG1, MYH6, GATA6, and LZTR1. Identified genes spanned all major stages of cardiogenesis, including developmental priming, cardiac progenitor specification, left-right axis formation, neural crest migration, outflow tract development, septation, and postnatal structural remodeling. Studies increasingly implicated ciliary dysfunction, transcriptional regulation, ribosomal biology, and multigenic inheritance in CHD pathogenesis. Emerging methodologies included stem cell-derived cardiac models, machine learning-based gene prioritization, and epigenetic analyses. CONCLUSIONS: Recent literature substantially expands the catalog of candidate genes that may be associated with CHD and highlights the biologic complexity underlying cardiac morphogenesis. Integration of genomic, developmental, and functional approaches will be essential to improve mechanistic understanding, refine genetic counseling, and support future precision medicine strategies for CHD.

Cardiac development↗

PubMed2026

Mitochondrial DNA diversity in Ecuadorian populations: Recurrence of variant 16136 within haplogroup B2.

The identification of lineage-defining variants, frequently found in the coding region of mitochondrial DNA (mtDNA), is essential for refining haplogroup classification. Most mtDNA studies in South American populations have focused on the control region (CR), which has provided important insights into population structure and maternal lineage origins, although information needed for more robust phylogenetic resolution has been neglected. This study investigates the maternal genetic structure of Ecuadorian populations by combining CR and whole mitogenome analyses. Sequences from the mtDNA CR were obtained from 461 individuals (253 Mestizos and 208 Native Americans), while complete mitogenomes were sequenced for 127 individuals to improve phylogenetic resolution by identifying lineage-defining variants present in coding region. Most mtDNA haplogroups in the two population groups analyzed were of Native American origin (A2, B2, B4, C1, D1, D4), with significant differences in the distribution of specific lineages between them. Among Mestizos, African haplogroups (all within the L branches) and Eurasian haplogroups (H, K, R, U) were detected at low frequencies, whereas no African lineages were observed among Native Americans. The results obtained highlighted a heterogeneity within Ecuadorian populations that must be considered when developing mtDNA haplotype databases for forensic purposes. Whole mitogenome sequences enabled the identification of variants that refined haplogroup classifications, provided a more accurate reconstruction of the maternal genetic diversity, and improve the discrimination between Native American and Asian maternal lineages within haplogroup B4b.

Humans↗

PubMed2025

Role of oxysterol 4β-hydroxycholesterol and liver X receptor alleles in pre-eclampsia.

BACKGROUND: Liver X receptors (LXRs) are expressed in placenta and may be associated with pre-eclampsia (PE). Oxysterols act as agonists for LXRs. We recently proposed a new blood pressure-regulating circuit with oxysterol 4β-hydroxycholesterol (4βHC) acting as a hypotensive factor via LXRs. MATERIALS AND METHODS: This study investigated the association between maternal plasma 4βHC, blood pressure (BP) indices, placental expression of LXR target genes, and patient characteristics using data from the Finnish Genetics of Pre-Eclampsia Consortium (FINNPEC) cohort. Plasma samples of 144 women with PE and 38 healthy pregnant controls as well as 44 PE and 40 control placental samples were available. In addition, genetic data from the FinnGen project was utilized to explore the associations of LXR alleles with PE and pregnancy hypertension. RESULTS: There were no significant associations between 4βHC and BP or maternal and perinatal characteristics in FINNPEC cohort. However, plasma 4βHC was inversely correlated with the maternal body mass index. There were no associations with the genetic variants of LXRs with PE in FinnGen. LXR target genes APOD, SCARB1, TGM2, and LPCAT3 were expressed differently between PE and normal pregnancies in placental samples of FINNPEC. CONCLUSIONS: Our results demonstrate that plasma 4βHC and genetic LXR variants do not play a major role in PE and BP regulation during pregnancy. However, key LXR target genes involved in lipid metabolism were expressed differently in normal and PE pregnancies. Further research is needed to understand the complexities of oxysterols, LXRs, and their potential contributions to placental function and pregnancy outcomes.

Humans↗

PubMed2026

Whole-exome sequencing-centered genetic evaluation for early-onset obesity in Chinese children: a retrospective single-center cohort.

BACKGROUND: Genetic causes of early-onset obesity remain undercharacterized in East Asian children. This study evaluated a whole-exome sequencing (WES)-centered diagnostic workflow in Chinese children with obesity onset before 5 years. METHODS: Consecutive children with body mass index above the 95th percentile and obesity onset before 5 years who completed structured inpatient assessment at a single center between February 2022 and December 2023 were retrospectively analyzed. Phenotyping included clinical, biochemical, oral glucose tolerance, cortisol rhythm, and liver assessments. Genetic testing combined WES, mitochondrial DNA analysis, multiplex ligation-dependent probe amplification (MLPA) for obesity-related imprinting loci, WES-based copy-number variant and runs-of-homozygosity analyses, and Sanger validation. Variants were interpreted according to the American College of Medical Genetics and Genomics/Association for Molecular Pathology (ACMG/AMP) criteria. RESULTS: Among 23 children, clinically relevant genetic findings were identified in 6 (26.1%): melanocortin-4 receptor (MC4R) c.831T>A (p.C277*), maternal uniparental disomy of 15q11-13, and four phenotype-correlated variants of uncertain significance in UCP3, BBS1, NCOA1, and SH2B1. The definitive/likely diagnostic yield, restricted to pathogenic or confirmed imprinting findings, was 8.7% (2/23). Findings involved leptin-MC4R signaling, BBSome function, fatty-acid oxidation, and chromosomal imprinting. Genetically positive children showed numerically higher alanine aminotransferase (ALT) and aspartate aminotransferase (AST), but differences were not statistically significant. BBS1 p.T374S was relatively enriched in East Asian reference data. CONCLUSIONS: A WES-centered integrated workflow detected heterogeneous genetic mechanisms in Chinese children with early-onset obesity, but variant of uncertain significance (VUS)-associated findings should be distinguished from confirmed diagnoses. Orthogonal methylation/MLPA and runs of homozygosity (ROH) analyses were necessary for imprinting diagnosis. Larger multicenter studies and functional validation are needed.

Chinese children↗

PubMed2026

Primary Mitochondrial-Disorders-Associated Nephropathy in Adulthood.

Oxidative phosphorylation (OXPHOS) is the main source of cellular adenosine triphosphate (ATP) production and depends on proteins encoded by both mitochondrial and nuclear DNA (nDNA). Pathogenic variants affecting this dual genetic control cause primary mitochondrial disorders (MIDs), which follow either maternal inheritance when they affect mitochondrial DNA (mtDNA) or autosomal inheritance when they affect nuclear-encoded mitochondrial proteins. Once considered predominantly pediatric conditions, these disorders are increasingly recognized in adults where their clinical presentation is heterogeneous and frequently underdiagnosed, requiring the involvement of various medical specialties.Because of their high energy requirements, kidneys are particularly vulnerable to primary MIDs. Tubular epithelial cells rely on OXPHOS for solute transport, whereas podocytes require sustained ATP production to preserve the glomerular filtration barrier. Although kidney involvement in adult primary MIDs has long been regarded as rare, emerging data indicate that primary MIDs-associated nephropathy (MIDAN) is more common than previously appreciated, yet remains under-recognized, as a cause of adult kidney disease. Renal manifestations include a broad spectrum of glomerular disorders-predominantly focal segmental glomerulosclerosis (FSGS), often associated with diabetes mellitus and sensorineural hearing impairment-as well as tubulo-interstitial nephritis (TIN), which may present as an isolated renal phenotype or as part of a multisystemic disorder.Advances in next-generation sequencing, including mitochondrial genome sequencing and exome or whole-genome sequencing, are transforming the diagnostic approach to MIDAN. Improved recognition of mitochondrial etiologies in adults with unexplained glomerular or tubulo-interstitial kidney disease is essential to optimize diagnosis, management, and genetic counseling.

adult↗

PubMed2026

Novel compound heterozygous POR variants in a neonate with Antley-Bixler syndrome and 46,XY DSD: a case report and literature review.

BACKGROUND: Cytochrome P450 oxidoreductase deficiency (PORD) is an ultra-rare autosomal recessive disorder within the congenital adrenal hyperplasia (CAH) spectrum, characterized by a broad clinical spectrum involving steroidogenesis defects, genital anomalies, and skeletal abnormalities. CASE PRESENTATION: We report a phenotypically female neonate with a 46,XY karyotype whose postnatal diagnostic evaluation was initiated after newborn screening revealed elevated 17-hydroxyprogesterone (17-OHP) concentration. The patient presented with mild hypertelorism, mild nasal hypoplasia, and low-set bilateral ears, along with female external genitalia consistent with disorder of sex development (DSD) and anal atresia. Radiological evaluation revealed femoral bowing and subsequent fracture. The craniofacial and skeletal abnormalities were consistent with the features of Antley-Bixler syndrome (ABS). Endocrine evaluation revealed elevated progesterone, markedly reduced testosterone, and secondary hyperaldosteronism. Genetic analysis identified three novel variants in the POR gene (NM_001395413.1): the patient harbored a paternal c.1187_1195dup (p.Pro396_Glu398dup) variant and two maternally inherited variants in cis, c.1447G>A (p.Gly483Ser) and c.1806 + 4_1806 + 28del. Protein structural modeling predicted that the p.Pro396_Glu398dup and p.Gly483Ser may disrupt the flavin adenine dinucleotide (FAD)-binding domain. RNA sequencing (RNA-seq) confirmed that the intronic variant c.1806 + 4_1806 + 28del caused aberrant splicing, resulting in partial intron retention and predicted impairment of the nicotinamide adenine dinucleotide phosphate (NADPH)-binding domain. According to American College of Medical Genetics and Genomics (ACMG) guidelines and incorporating functional evidence, c.1187_1195dup and c.1806 + 4_1806 + 28del were reclassified as likely pathogenic (LP), whereas c.1447G>A remained a variant of uncertain significance (VUS). CONCLUSIONS: This study describes a neonate with PORD caused by three novel POR variants and expands the known clinical spectrum of PORD by identifying rare manifestations including anal atresia and hearing loss. RNA-seq provided valuable functional evidence for variant interpretation and facilitated accurate molecular diagnosis. These findings highlight the importance of integrating genetic phasing, transcript-level functional analysis, and comprehensive clinical evaluation for precise diagnosis and counseling in rare endocrine disorders.

Humans↗

PubMed2024

Two novel TMEM67 variations in a Chinese family with recurrent pregnancy loss: a case report.

BACKGROUND: Recurrent pregnancy loss (RPL) is a common pregnancy complication that brings great pain to pregnant women and their families. Genetic factors are an important cause reason of RPL. However, clinical research on monogenic diseases with recurrent miscarriage is insufficient. CASE PRESENTATION: Here we reported a Chinese family with RPL and genetic analysis of the abortion and parents. A paternally inherited heterozygous missense variant c.1415T > G (p.V472G) and a maternally inherited heterozygous nonsense variant c.2314del (p.M772*) in TMEM67 gene were identified by trio-exome sequencing. c.2314del (p.M772*) generated a premature stop codon and truncated protein, was classified as "pathogenic". c.1415T > G (p.V472G) located in extra-cellular region, was classified as "likely pathogenic". Biallelic variants in TMEM67 gene cause lethal Meckel syndrome 3, consistent with the proband's prenatal phenotype. CONCLUSION: The current study of the Chinese family expands the pathogenic variant spectrum of TMEM67 and emphasizes the necessity of exome sequencing in RPL condition.

Adult↗

PubMed2026

[Pathogenicity analysis and prenatal genetic counseling for five Chinese pedigrees harboring a hemizygous c.-32C>G variant of FGF13 gene].

OBJECTIVE: To explore the pathogenicity and prenatal counseling strategies for five Chinese pedigrees harboring a hemizygous c.-32C>G (NM_001139500.2) variant of fibroblast growth factor 13 (FGF13) gene. METHODS: Five Chinese pedigrees found to carry a hemizygous c.-32C>G variant of the FGF13 gene at the Prenatal Diagnosis Center of Henan Provincial People's Hospital between January 2024 and January 2025 were selected as study subjects. The pedigrees had undergone prenatal diagnosis for a family history of genetic disorders, abnormal fetal ultrasound findings, or advanced maternal age. A retrospective analysis was carried out, wherein clinical data for all members of the pedigrees were obtained through the medical records system and outpatient visit system. Peripheral blood samples were collected from all pedigree members, and amniotic fluid samples were obtained from the probands. Following extraction of genomic DNA, prenatal diagnosis was performed using chromosomal microarray analysis (CMA) and trio whole-exome sequencing (trio-WES). Sanger sequencing was used to determine the carrier status for the candidate variant, and Mini-Mental State Examination (MMSE) was used to assess the cognitive function of hemizygous individuals carrying the FGF13 gene c.-32C>G variant. Pathogenicity of candidate variant was assessed based on guidelines from the American College of Medical Genetics and Genomics (ACMG). This study was approved by the Medical Ethics Committee of the hospital (Ethics No.: 2021-171). RESULTS: CMA and trio-WES revealed no pathogenic variants in all probands, whilst trio-WES and Sanger sequencing had identified 11 male individuals carrying a hemizygous c.-32C>G variant of the FGF13 gene from the five pedigrees, which included six adult males, a young boy, and four fetuses. One fetus had undergone termination of pregnancy due to hydrocephalus, one was born pre-term at 34+1 weeks of gestation owing to maternal hypertension, and other two were delivered at full term. Follow-up of the survived males revealed no phenotypic manifestations related to language or intellectual impairment. Among these, three adult males underwent the MMSE assessment, all of whom showed normal cognitive function. Search of the gnomAD database suggested the carrier frequency of FGF13 c.-32C>G variant in the East Asian population to be 0.125%, with 11 hemizygous males documented. Three male patients harboring the variant showed severe intellectual disability. Both in vitro and in vivo studies suggested that it could reduce the translation levels of FGF13 protein. Based on the ACMG guidelines, it was classified as variant of uncertain significance (BS4+PS3_Supporting). CONCLUSION: There is insufficient evidence to classify the FGF13 c.-32C>G as a pathogenic variant in clinical practice, and its presence should not be considered an indication for pregnancy termination due to major birth defects.

Adult↗

PubMed2026

The long road to diagnosis: recessive PMPCB deficiency hidden behind a dominant familial VCP defect.

Multiple mitochondrial dysfunctions syndrome 6 (MMDS6), caused by biallelic likely pathogenic variants in PMPCB, is an extremely rare autosomal recessive childhood-onset neurodegenerative disorder, with only six reported cases to date, most resulting in early mortality. Pathogenic variants in VCP cause multisystem proteinopathy 1 (MSP1), an autosomal dominant adult-onset disorder encompassing inclusion body myopathy (IBM), frontotemporal dementia (FTD), and amyotrophic lateral sclerosis (ALS), typically presenting in mid-adulthood. We describe a 23-year-old female with two likely pathogenic variants presumed to be in trans in PMPCB and a co-occurring pathogenic VCP variant. She was misdiagnosed for over 20 years with early-onset VCP-related neurodegeneration due to a maternal family history of ALS. Her disease began at birth with microcephaly and progressed throughout childhood, including developmental regression, cerebellar and cerebral atrophy, optic atrophy, seizures, spasticity, dysarthria, and loss of ambulation. Initial genetic testing identified only the familial VCP variant. Updated genomic sequencing at age 23 revealed two likely pathogenic PMPCB variants, strong supporting a diagnosis of MMDS6. Her clinical features closely align with previously reported MMDS6 cases and are inconsistent with the typical adult-onset phenotype of VCP-associated disorders. While she shares overlapping features with VCP-related disease (limb-girdle weakness, spasticity, FTD), the timing and severity of her neurodevelopmental findings support MMDS6 as the primary diagnosis. Early mitochondrial dysfunction may predispose her to an accelerated or more severe future VCP-associated phenotype. This is the first report of combined likely pathogenic and pathogenic variants in PMPCB and VCP respectively, expanding the phenotypic spectrum of both disorders. The case underscores the necessity of periodic re-evaluation with advanced genetic testing, highlights important ethical and familial implications, and informs future diagnosis and management of patients with overlapping rare genetic conditions.

Dual molecular diagnosis↗

PubMed2026

Analysis of Genetic Factors in a Family With Short Stature.

BACKGROUND: To elucidate the genetic underpinnings of short stature in a familial cohort of five individuals. METHODS: A family with a history of short stature from Zhongnan Hospital of Wuhan University was the subject of this study. Peripheral blood samples were collected from family members for whole exome sequencing and Sanger sequencing to identify genetic anomalies. RESULTS: The male proband, aged 3 years and 10 months, had significant growth retardation, with a height of 91 cm (< 3rd percentile) and a weight of 13 kg (< 3rd percentile). Whole exome sequencing identified a missense mutation in the COL1A2 gene (c.577G>A, p.Gly193Ser) with maternal inheritance. Sanger sequencing confirmed this mutation in the mother and half-sister. According to American College of Medical Genetics and Genomics (ACMG) guidelines, this variant was classified as likely pathogenic. Additionally, a heterozygous mutation in the GH1 gene (c.291+1G>A) was detected in the father and grandfather, contributing to the familial short stature phenotype. CONCLUSION: In this family, we identified that variants in the COL1A2 and the GH1 can each cause short stature. This reflects both the genetic consistency and complexity of short stature, which is highly dependent on comprehensive genetic testing.

Humans↗

PubMed2026

Genome-wide association study of patterns of perinatal exposure to polyunsaturated fatty acids from the EDEN mother-child cohort.

The genetic determinants of polyunsaturated fatty acid (PUFA) status during the perinatal window require deeper understanding. We conducted a genome-wide association study of perinatal PUFA patterns in 1352 mother-child pairs from the French EDEN cohort using maternal genotype data. Five perinatal PUFA patterns had been previously derived using PUFA levels measured in maternal blood, cord blood, and colostrum simultaneously. We used linear regression models assuming additive genetic effects to assess the associations between common SNPs and each pattern, adjusting for maternal age, study center, and genetic ancestry. Pattern 1 "High omega-3 Long-chain (LC)-PUFAs, low omega-6 LC-PUFAs" was not associated with any genetic variants. Patterns 2 to 5-"Omega-6 LC-PUFAs," "Colostrum LC-PUFAs," "Omega-6 precursor (LA) and DGLA," and "LA and colostrum ALA"-were strongly associated with variants in the FADS gene cluster. The strongest association was observed between Pattern 4 "Omega-6 precursor (LA) and DGLA," and rs174546 located on FADS1 gene region (β (SE) = 0.80 (0.034), p < 10⁻102). No other robust association was found with other genes. These findings underscore the main contribution of FADS variants to the variability of four specific perinatal PUFA patterns in our cohort. This study should be replicated in larger, ancestrally diverse populations beyond individuals of European descent.

EDEN cohort↗

PubMed2026

A Case Report of Infantile Dopa-Responsive Dystonia Onset With Sleep Disorder Complicated With Autism Spectrum Disorder.

AIMS/BACKGROUND: Dopa-responsive dystonia (DRD) is a rare genetic disorder with complex and diverse clinical manifestations, resulting in a high rate of misdiagnosis. This case report describes an infantile case of DRD complicated by autism spectrum disorder (ASD), initially presenting with a sleep disorder. We aim to summarize its clinical manifestations, diagnostic process, treatment, and follow-up outcomes in order to improve clinical understanding of this disease. CASE PRESENTATION: A retrospective analysis was performed on a male infant who was treated at Jinhua Maternal and Child Health Care Hospital in 2020. The patient presented at one month of age with sleep disturbances, delayed motor development, and intermittent upward deviation of the eyes. Genetic testing identified two heterozygous pathogenic variants in the tyrosine hydroxylase (TH) gene. Among them, the c.738-2A>G variant was not recorded in the Exome Aggregation Consortium (ExAC), Genome Aggregation Database (gnomAD), or 1000 Genomes Asian population databases. During follow-up, the patient was also found to have comorbid ASD. RESULTS: Genetic testing confirmed biallelic TH mutations, establishing the diagnosis of infantile DRD. The patient exhibited marked clinical response to levodopa/benserazide, though dose titration was required with growth. CONCLUSION: For infants with unexplained sleep disorder accompanied by delayed motor development, genetic testing should be performed as early as possible to facilitate the identification of the root cause and implement timely treatment. In addition, close follow-up should be conducted to detect comorbid neurodevelopmental disorders.

Humans↗

PubMed2026

Maternal DNA repair safeguards genome stability during the oocyte-to-embryo transition.

De novo mutations are a major source of genetic variation and disease risk, yet the developmental timing and mechanisms underlying their origin require further investigation. While germ cells have traditionally been considered the primary source of these mutations, increasing evidence suggests that a substantial fraction arise after fertilization. Here, we investigated the role of maternal DNA repair in shaping mutagenesis during this critical window by using a mouse model with oocyte-specific disruption of the homologous recombination factor RAD51 and a combination of cellular and molecular analyses. Loss of maternal RAD51 led to the accumulation of DNA double-strand breaks in oocytes without impairing their growth, meiotic maturation, or fertilization competence. In contrast, embryos derived from RAD51-deficient oocytes exhibited increased DNA damage and developmental delay during early cleavage stages. Whole-genome sequencing revealed a significant increase in de novo variants in offspring, the majority displaying intermediate allele frequencies consistent with post-zygotic mosaic mutations. These findings confirm that maternal DNA repair safeguards genome stability across the oocyte-to-embryo transition and identify early embryogenesis as a major source of de novo mutations, with implications for reproductive biology and the origins of genetic diseases.

DNA↗

PubMed2026

Digenic HNF1A and ABCC8 variants provide mechanistic insight into early-onset diabetes.

CONTEXT: Oligogenic inheritance in maturity-onset diabetes of the young (MODY) remains poorly characterized, and the contribution of multiple candidate variants to disease pathogenesis is incompletely understood. OBJECTIVE: To investigate the pathogenicity and mechanistic contribution of multiple MODY gene variants identified in a MODY-like family and determine their role in early-onset diabetes. METHODS: Comprehensive genetic analysis of known MODY genes was performed in a MODY-like family. Functional effects of HNF1A and HNF1B variants were assessed using luciferase reporter assays in HEK293T cells. Functional characterization of ABCC8 variants included Kir6.2-dependent thallium (Tl+) flux assays, sulfonylurea responsiveness, and channel stability. RESULTS: Four variants in 3 MODY genes were identified in the proband: novel HNF1A p.Ser551Lysfs*2, HNF1B p.Glu102Ala, and ABCC8 p.Arg298Cys and p.Arg521Gln. Functional analysis showed that HNF1A p.Ser551Lysfs*2 retained approximately 5% of wild-type transactivation activity, consistent with loss-of-function, whereas HNF1B p.Glu102Ala and ABCC8 p.Arg521Gln exhibited wild-type-like function. In contrast, ABCC8 p.Arg298Cys reduced channel activity to 77% of wild-type levels while preserving sulfonylurea responsiveness. Segregation analysis identified HNF1A p.Ser551Lysfs*2 and ABCC8 p.Arg298Cys in affected parents. The proband, who inherited both pathogenic variants, developed diabetes earlier than either parent and was exposed to maternal hyperglycemia in utero, which may also have contributed to this early onset. CONCLUSION: Functional characterization distinguishes pathogenic from variants of unknown significance and supports digenic inheritance of HNF1A and ABCC8. Their additive effects, together with intrauterine hyperglycemia, likely accelerated disease onset. This study provides mechanistic evidence for oligogenic contributions to MODY and expands the genetic architecture of early-onset diabetes.

Humans↗

PubMed2026

Genomic early growth mechanisms of two endangered Mexican spruces.

This study elucidated the genomic basis of family-level growth variance in the critically endangered endemic Mexican spruces Picea martinezii and P. mexicana by: (i) analyzing family- and population-level variations in seedling basal diameter and height after 12 months of growth under common garden conditions and seed weight as maternal provisioning trait; and (ii) identifying genomic loci (SNPs) associated with these traits. Despite limited sample sizes (77 and 74 families representing all known populations of both species), 32 and 10 outlier SNPs were identified yielding 17 and six annotated candidate genes in P. martinezii and P. mexicana, respectively. These genes showed contrasting multivariate associations suggesting species-specific hypothesized growth strategies at the family level: defense-oriented framework in P. martinezii and plasticity-driven response in P. mexicana. Notably, several candidate genes encode key components of growth hormone pathways, including a gibberellin-regulated protein, a cytokinin hydroxylase and the AP2-like transcription factor ANT, providing valuable insights into how maternal genetic variation corresponds to the hormonal pathways that govern cell proliferation and organ size in the progeny. Integration of these findings with the contrasting demographic histories of both species revealed that population bottlenecks enhance the detectability of growth-associated variants by reducing background genetic variation. These genomic resources provide actionable information for prioritizing conservation measures, implementing assisted gene flow to maintain adaptive potential under climate change and designing future breeding programs. With 80.9-99.6% sequence identity to conserved Picea abies homologs, these findings may extend across the genus.

Picea↗

PubMed2026

Placental Site Trophoblastic Tumor Acquires Immune Functions by Incorporating Host Maternal Genes.

Although it was proposed that cell fusion of cancer cells with leukocytes creates mobile hybrids with a metastatic phenotype, it has been difficult to genetically confirm cell fusion events in human cancer in vivo. Here, we experienced 4 cases of placental site trophoblastic tumor (PSTT) that produced immunoglobulin (Ig). Three cases showed recurrence and responded well to pembrolizumab therapy. Among them, we could analyze temporal changes in the genetic profiles on one case of daughter-derived PSTT, which relapsed after pembrolizumab therapy. In this case, we found that PSTT incorporated the exogenous genes from host maternal cells. The rearrangement patterns of Ig genes and protein expressions sequentially increased. By analyzing single-nucleotide variants, PSTT incorporated daughter-non-inherited maternal alleles (DNIMA), including the Ig lambda and HLA-DQA2 loci. Protein expressions of TLR10 and SIGLEC10 increased during tumor progression concomitantly with DNIMA incorporation. DNIMA mapping indicates the incorporation of exogenous maternal genes was widely distributed through the whole chromosomes, suggesting the involvement of cell fusion in gene transfer mechanisms. These findings indicate that PSTT sequentially incorporated exogenous genes from maternal cells to express immune-related molecules and suggest that cancer cells acquired B cell-related functions, including Ig production by cell fusion with host immune cells.

Humans↗