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[Study of a patient with azoospermia due to variant of MOV10L1 gene].

OBJECTIVE: To explore the clinical and genotypic characteristics of a patient with Sertoli cell-only syndrome (SCOS) due to variants of MOV10L1 gene. METHODS: A 27-year-old patient with Non-obstructive azoospermia (NOA) underwent routine semen analysis. Serum levels of follicle-stimulating hormone (FSH), luteinizing hormone (LH), progesterone (P), estradiol (E2), prolactin (PRL), and testosterone (T) were determined by chemiluminescence assays. Peripheral blood samples were collected for G-banded karyotyping analysis. Multiplex PCR fluorescence detection was used to screen for AZF gene microdeletions. Whole exome sequencing (WES) and Sanger sequencing were performed simultaneously. Testicular biopsy tissues were subjected to Hematoxylin-Eosin (HE) staining to assess seminiferous tubule cell composition, and MOV10L1 protein expression was detected by immunohistochemical staining. Bioinformatics tools were employed to predict the pathogenicity of variants and their impact on protein structure and function. This study was approved by the Medical Ethics Committee of the Guangdong Institute of Reproductive Sciences [Ethics No.: 2023(01)]. RESULTS: The patient's two semen analyses had failed to detect any sperm. Hormone tests indicated elevated FSH (22.32 mIU/mL) and PRL (397.6 mIU/mL), while T (3.68 nmol/L) and E2 (38.32 pmol/L) were reduced. Chromosomal karyotyping revealed 46,XY, and no AZF gene deletion was detected. WES and Sanger sequencing detected compound heterozygous variants of the MOV10L1 gene, including a c.345C>A (p.C115X) nonsense variant and a c.3323C>T (p.T1108I) missense variant, with the former being unreported previously. HE staining showed only Sertoli cells in the seminiferous tubules, confirming the diagnosis of SCOS. Immunohistochemical staining revealed absent MOV10L1 protein expression in the testicular tissue. Based on the guidelines from American College of Medical Genetics and Genomics (ACMG), the c.345C>A (p.C115X) was classified as a pathogenic variant (PVS1+PM2_Supporting+PP4), while the c.3323C>T (p.T1108I) was deemed variant of uncertain significance (PM2_Supporting+PP3_Supporting+PP4). Bioinformatics analysis demonstrated that c.345C>A (p.C115X) may cause premature termination of protein translation, while c.3323C>T (p.T1108I) may disrupt the hydrophobicity of the RNA helicase domain, reducing the active pocket volume and decreasing its affinity for MILI protein. CONCLUSION: This study has diagnosed a case of SCOS due to compound heterozygous variants of the MOV10L1 gene, which also enriched its mutational spectrum.

Humans↗

[Chromosome subtelomeric analysis by FISH in patients with mental retardation].

OBJECTIVE: To assess subtelomeric chromosome anomalies in patients with idiopathic mental retardation (MR). METHODS: Subtelomeric screening was performed in 46 patients with undiagnosed mental retardation. The patients were selected based on the following criteria: (1) MR with two or more of the following conditions: dysmorphic features, prenatal growth retardation, postnatal growth abnormalities, a suggestive family history; (2) chromosome karyotype at the level >450 bands being normal; (3) exclusion of other identified genetic or environmental diagnosis. Fluorescence in situ hybridization (FISH) was performed using ToTelVysion DNA probes. Abnormal findings were confirmed by FISH with a specific subtelomeric probes and family studies were carried out to determine its inheritance. RESULT: Clinically significant aberrations were detected in two cases with 6q and 2q terminal microdeletion. The deletion in one case was inherited from a similarly affected father. Subtle chromosomal subtelomeric abnormalities occurred with a frequency of 7.6% in children with moderate to severe mental retardation and of 3.0% in the children with mild retardation. CONCLUSION: The results suggest that cryptic abnormalities of the ends of chromosomes might represent a significant cause of mental retardation, and screening for subtelomeric rearrangements might be warranted in children with unexplained mental retardation.

Adolescent↗

Deletion 3q in two patients with blepharophimosis-ptosis-epicanthus inversus syndrome (BPES).

BACKGROUND: Blepharophimosis-ptosis-epicanthus inversus syndrome (BPES) is an autosomal dominant condition mapped to chromosome 3q23. There are several reports of chromosomal abnormalities involving this region with a resultant phenotype that includes BPES. METHOD: We reassessed two unrelated boys ages 3 and 5 with BPES and associated nonocular abnormalities. Karyotype, which had been previously reported as normal, was repeated using high-resolution banding techniques, to look specifically at 3q23. Clinical findings were tabulated and compared with previously reported cases. RESULTS: Both patients proved to have interstitial deletions of chromosome 3, the first involving bands q22.2q25.1 and the second q22.2q24. The first patient exhibited prenatal and postnatal growth retardation, with global developmental delay, while the second patient had normal growth and development except for speech delay. Both had dysmorphic facies with BPES, flat philtrum, a thin upper lip, and small chin. In addition, the first boy had an inguinal hernia and hypospadius; the second boy had abnormal auricles and metatarsus adductus. The eight cases of interstitial deletions of 3q2 and six rearrangements involving this region have a remarkably similar phenotype. CONCLUSIONS: Deletion of 3q23 is a recognizable contiguous gene syndrome. Microdeletions of 3q23 should be ruled out in any sporadic case of BPES especially if there are associated nonocular abnormalities.

Blepharophimosis↗

Unilateral Peters' anomaly in a patient with DiGeorge syndrome.

We report a case of unilateral Peters' anomaly in a 3-month-old infant with a microdeletion in chromosome 22q11.2, a finding not previously described. This anterior segment anomaly can be explained by a problem in neural crest development, as neural crest cells are known to play a role in the developmental defects of this disorder.

Chromosome Deletion↗

DNA fluorescent probes for diagnosis of velocardiofacial and related syndromes.

OBJECTIVE: To study the usefulness of fluorescent in situ hybridization (FISH) with the DNA probe D22S75 for detecting microdeletions in chromosome 22q11.2 in metaphases from patients with features of "CATCH 22" (cardiac anomalies, abnormal facies, thymic hypoplasia or aplasia, cleft palate, and hypocalcemia). METHODS: High-resolution chromosome analysis and FISH were performed on metaphases from 10 control subjects, 42 patients with features of CATCH 22, and 6 parents of children with CATCH 22. Patients were screened for conotruncal heart defect, palatal abnormality, and facial features. We correlated the phenotype, karyotype, and deletion of a D22S75 locus. RESULTS: Specimens from nine patients with one or more features of CATCH 22 had a single hybridization signal for D22S75, indicating a deletion of chromosome 22q11.2. Four patients had all the major features of the syndrome and a chromosomal deletion. Thirteen patients had two CATCH 22 features, five of whom had a deletion. None of the 25 patients with a single CATCH 22 feature had a deletion. One patient with a deletion detected by FISH also had a deletion noted on high-resolution banding. All six parents who had blood samples studied by FISH had normal hybridization patterns. CONCLUSION: FISH is a useful adjunct to chromosome analysis for assessing patients with features of CATCH 22. Detecting a chromosomal deletion by FISH provides a definitive diagnosis and helps to ensure appropriate medical management and genetic counseling.

Abnormalities, Multiple↗

[Clinical findings and immunologic variability in 9 patients with DiGeorge syndrome].

BACKGROUND: DiGeorge syndrome is characterized by developmental defects of the heart, parathyroid glands and thymus. AIM: To describe the clinical variability of DiGeorge syndrome and its relation with immunodeficiency. PATIENTS AND METHODS: A three years retrospective chart review from three hospitals of Santiago, Chile was conducted. We included patients with neonatal diagnosis of DiGeorge syndrome. Clinical and immunologic data were collected from their initial evaluation. RESULTS: We found 9 patients with DiGeorge syndrome. All had dysmorphic facies, hypocalcemia and congenital heart disease. Three patients had hypoparathyroidism, 4 had interrupted aortic arch type B, 4 had tetralogy of Fallot and 1 had coarctation of aorta. Six patients had other malformations and associated diseases. FISH studies, performed in 8 patients, found the 22q11.2 microdeletion in all. Most patients had low CD3, CD4 and CD8 T cell counts, that ranged for CD3 T cells, between 256/mm3 and 3,664/mm3, for CD4 T cells, between 224/mm3 and 2,649/mm3, for CD8 T cells, between 26/mm3 and 942/mm3. Three patients had CD4 T cells counts <400/mm3 and one had a phytohemagglutinin stimulation index <10. Airway malformations and primary hypoparathyroidism were present in 3 out of 4 patients that died before 18 months compared with the surviving patents (p=0.048). CONCLUSIONS: We found variable clinical manifestations as well as CD3, CD4 and CD8 T cell counts in patients with DiGeorge syndrome. Airway malformations were associated with a higher mortality.

Chromosomes, Human, Pair 22↗

[Clinical, genetic and molecular features in 45 patients with Prader-Willi syndrome].

BACKGROUND: Prader-Willi syndrome (PWS) is a neurogenetic disease characterized by neonatal hypotonia, retarded mental and motor development, hypogonadism, hyperphagia, morbid obesity and dysmorphic facial features. It has an incidence of 1:12.000-15.000 newborns and is caused by abnormalities in genes located in 15q11q13. PWS is one of the most frequent genetic disorders and microdeletion syndromes. It is also the most common cause of obesity from genetic origin and it was the first disease in which imprinting and uniparental disomy were recognized as cause of genetic disorders. Seventy to seventy five percent of PWS cases are due to 15q11q13 deletions, 20-25% to uniparental disomy and 1% to mutations in the imprinting center. AIM: To analyze the clinical, genetic and molecular features of patients with PWS, seen at one institution. PATIENTS AND METHODS: Retrospective review of 45 patients (27 males) with PWS seen at the Genetics Outpatient Clinic at INTA. RESULTS: Twenty three (51.1%) patients had a deletion, 13 (28.9%) patients did not have a deletion. In nine patients, fluorescence in situ hybridization (FISH) study was not performed, therefore the presence of deletion was unknown. The clinical score was 8 points for patients younger than 3 years (n=11) and 11.5 points for patients older than 3 years (n=34); for patients aged 12 months or less, the clinical score was 7 points. Mean clinical score was 11 points for patients with deletion and 10 points for patients without deletion. CONCLUSIONS: Most patients with PWS have a deletion; the phenotype depends on age and the clinical score is useful for Chilean patients with PWS.

Adolescent↗

Methylphenidate treatment for attention-deficit/hyperactivity disorder in children and adolescents with velocardiofacial syndrome: an open-label study.

BACKGROUND: Velocardiofacial syndrome (VCFS) is a common microdeletion syndrome associated with psychiatric morbidity and developmental disabilities. Although attention-deficit/hyperactivity disorder (ADHD) is the most common psychiatric problem associated with VCFS, there are no reports on methylphenidate treatment in this patient population. Indeed, clinicians have commonly avoided the use of methylphenidate in children with VCFS because of concerns about ineffectiveness or psychotic exacerbation. METHOD: Forty subjects of mean +/- SD age 11.0 +/- 5.0 years with VCFS were assessed for DSM-IV diagnoses using the Schedule for Affective Disorders and Schizophrenia for School-Aged Children, Present and Lifetime Version, and its extended ADHD module (K-SADS-P-ADHD). Those found to have comorbid ADHD were treated with methylphenidate, 0.3 mg/kg once daily. Treatment efficacy was evaluated after 4 weeks with the K-SADS-P-ADHD, the Conners' Abbreviated Teacher Questionnaire, and the Conners' Continuous Performance Test. Side effects were evaluated with a modified version of the Barkley Side Effects Rating Scale. RESULTS: Of the 18 subjects (45%) diagnosed with ADHD, 12 agreed to participate in the study. Their ADHD symptoms, both behavioral and cognitive, improved significantly with treatment. None of the patients showed clinical worsening or psychotic symptoms. Side effects were usually mild and did not warrant discontinuation of methylphenidate. The most common side effects were anorexia and depressive-like symptoms. CONCLUSION: This open-label study indicates that methylphenidate is effective and safe in patients with VCFS. Therefore, its current limited use in this population seems to be unjustified. Larger, controlled clinical and pharmacogenetic studies are needed to confirm these findings.

Adolescent↗

A case of gonadal dysgenesis, breast development, Graves' disease, and low bone mass.

OBJECTIVE: To describe a case of XY gonadal dysgenesis with Tanner stage 4 breast development in the absence of a hormone-producing gonadal neoplasm and with Graves' disease and low bone mass. METHODS: The clinical features, laboratory results, and cytogenetic findings in the patient are presented, and the potential mechanisms of breast development are discussed. A MEDLINE search was performed, and related articles in the English-language literature published between 1955 and 2001 were reviewed. RESULTS: A 23-year-old African American woman was referred to the University of Louisville Hospital for evaluation of hyperthyroidism. About 4 months before this referral, hyperthyroidism was diagnosed, and treatment with methimazole was initiated. She continued to have thyrotoxicosis. Additionally, systemic review disclosed a history of primary amenorrhea. Physical examination revealed a tall phenotypic female patient with Tanner stage 4 breast development. Pelvic examination showed normal findings except for sparse pubic hair. Laboratory evaluation confirmed the diagnosis of Graves' disease as well as primary gonadal failure. Pelvic ultrasonography revealed a small uterus and bilateral adnexal masses (0.9 by 0.6 cm). On chromosomal analysis, a 46,XY karyotype was found. Further analysis of Y-DNA by polymerase chain reaction confirmed the presence of an intact Y chromosome, and no microdeletions were identified. Dual-energy x-ray absorptiometry demonstrated a Z-score of -4.7 and -4.2 at the lumbar spine and right hip, respectively. Graves' disease was successfully treated with (131)I. Laparoscopy was performed to resect streak gonads. On histologic examination, no typical ovarian, testicular, or neoplastic tissue was identified. The breast development in this patient remains unexplained. CONCLUSION: To the best of our knowledge, this is the first case report of a tall XY female patient with breast development in the absence of a hormone-producing gonadal neoplasm and without clearly identifiable gonads. Breast development was most likely related to estrogens, possibly produced by either streak gonads at the time of puberty or peripheral conversion of androgens, or to increased sensitivity of breast tissue to estrogens. Graves' disease is likely coincidental and could contribute to bone loss in such subjects.

Absorptiometry, Photon↗

Epigenetics and cancer: altered chromatin remodeling via Snf5 loss leads to aberrant cell cycle regulation.

The term 'epigenetics' refers to heritable changes in gene function that occur in the absence of any change in DNA sequence. Perturbations of epigenetic gene regulation may play a critical role in the genesis of most, if not all, cancers. These alterations include changes in covalent modifications of DNA and histones as well as non covalent changes in nucleosome positioning. Covalent epigenetic modifications have been the main focus of cancer investigation, perhaps because they are more readily assayed and understood than non covalent modifications. Recently, evidence has emerged demonstrating that perturbation of complexes that remodel the structure of chromatin by mobilizing nucleosomes may have a key role in tumor suppression and oncogenic transformation. For example, Snf5 (Ini1/Baf47/Smarcb1), a core component of the Swi/Snf ATPase chromatin remodeling complex, is a potent tumor suppressor that is specifically inactivated in lethal childhood cancers. Notably, these cancers may serve as a paradigm for epigenetic cancers as, despite their extremely aggressive nature, the majority have an entirely normal karyotype with only microdeletions at the Snf5 locus. Recent investigations have shed light upon the mechanistic basis of Snf5 function by demonstrating that Snf5 and the Swi/Snf complex regulate the cell cycle and cooperate with p53 to prevent oncogenic transformation.

Animals↗

Proficiency testing for laboratories performing fluorescence in situ hybridization with chromosome-specific DNA probes.

OBJECTIVE: To assess laboratory performance, use, and limitations in the joint College of American Pathologists and American College of Medical Genetics proficiency testing program for laboratories performing cytogenetic tests based on fluorescence in situ hybridization (FISH). DATA SOURCES: Eight proficiency surveys dealing with FISH detection of microdeletions or microduplications, aneuploidy in interphase cells, gene amplification, and neoplasm-specific translocations. Participating laboratories used their own DNA probes (commercial or home-brew), hybridization methods, and analytic criteria to answer clinical questions about cases represented by slides included in the survey materials. They also described their test results according to the International System for Human Cytogenetic Nomenclature (ISCN) and answered supplementary questions relating to their experience with the subject test systems. DATA EXTRACTION: In addition to evaluating diagnostic accuracy, we evaluated survey use, laboratory experience, variation in methodologic approach, and the practicality of using ISCN nomenclature for describing test results. SYNTHESIS AND CONCLUSIONS: With the exception of one challenge, at least 80% of the participants reached the correct diagnostic conclusion. In the sole exception, there was still a consensus of 91.7% of participants with the same (albeit erroneous) diagnostic conclusion. The overall outstanding performance of participating laboratories clearly shows the reliability of current FISH methods. Despite the fact that a large number of laboratories reported little or no experience with the specific test systems, the overwhelming majority performed very well. This result shows that the program's strategy of targeting classes of abnormalities (vs a single abnormality associated with a specific disease) did not put at a disadvantage participants who did not routinely perform all of the potential tests in the class. The extraordinary variation in ISCN descriptions submitted by participants showed that the existing system for human cytogenetic nomenclature is not suitable for facile communication of FISH test results.

Chromosome Aberrations↗

Syndromes of glucocorticoid resistance.

Glucocorticoid resistance results from the partial, albeit apparently generalized, inability of glucocorticoids to exert their effects on target tissues. The condition is associated with compensatory increases in circulating pituitary corticotropin and cortisol, with the former causing excess secretion of both adrenal androgens and adrenal steroid biosynthesis intermediates with salt-retaining activity. The manifestations of glucocorticoid resistance vary from chronic fatigue (perhaps a result of glucocorticoid deficiency in the central nervous system) to various degrees of hypertension with or without hypokalemic alkalosis or hyperandrogenism, or both, caused by increased cortisol and other salt-retaining steroids and adrenal androgens, respectively. In women, hyperandrogenism can result in acne, hirsutism, menstrual irregularities, oligoanovulation, and infertility; in men, it may lead to infertility and in children, to precocious puberty. Different molecular defects, such as point mutations or a microdeletion of the highly conserved glucocorticoid receptor gene, alter the functional characteristics or concentrations of the intracellular receptor and appear to cause glucocorticoid resistance. The extreme variability in the clinical manifestations of glucocorticoid resistance and its mimicry of many common diseases can be explained by the overall degree of glucocorticoid resistance, differing sensitivity of target tissues to mineralocorticoids or androgens or both, and perhaps different biochemical defects of the glucocorticoid receptor, with selective resistance of certain glucocorticoid responses in specific tissues. The various different symptoms of classic glucocorticoid resistance and the theoretical potential of this condition to appear surreptitiously emphasize the importance of the glucocorticoid receptor in the pathogenesis of human disease.

Drug Resistance↗

Molecular analysis of 1p32 genetic involvement in pediatric T-cell non-Hodgkin's lymphoma.

BACKGROUND AND OBJECTIVE: T-cell acute lymphoblastic leukemia (T-ALL) and lymphoblastic T-cell non-Hodgkin's lymphoma (T-NHL) are closely related disorders, and distinguishing between the two may be difficult. Cytogenetic investigations of large NHL series reported different recurring chromosomal alterations. Among these, aberrations of chromosome 1p seem to be associated with T-cell differentiation, the region most frequently involved in breakpoints being band 1p32-36. Deletions and translocations involving the same chromosomal region are frequently observed in T-ALL, in which one of the most common genetic changes is the breakage of the TAL1 gene, mapped to the 1p32 chromosomal region. The objective of this study was to assess the possibility of TAL1 involvement also in T-NHL. DESIGN AND METHODS: A series of 17 pediatric T-NHL patients was molecularly characterized by microsatellite markers analysis and by TAL1 gene microdeletions. RESULTS: TAL1 gene rearrangement was found in one case, while loss of heterozygosity (LOH) and microsatellite instability (MI) was identified in another case. INTERPRETATION AND CONCLUSIONS: Overall our findings indicate that, differently from T-ALL, neither TAL1 gene involvement nor LOH or MI at 1p32 appear particularly relevant in the oncogenic process of T-NHL transformation.

Adolescent↗

Deletion mapping and X inactivation analysis of a non-specific mental retardation gene at Xp21.3-Xp22.11.

We report on deletion mapping and X inactivation analysis of a gene for X linked non-specific mental retardation (MRX) at Xp21.3-Xp22.11, on the basis of molecular studies in two families with Xp microdeletions involving the DAX-1 gene. In family A, mental retardation (MR) was profound in the older brother with an episode of adrenal crisis, severe in the younger brother with no episode of adrenal crisis, and mild to moderate in the sister and the mother with no signs of adrenal hypoplasia. In family B, MR was absent in the male patient with adrenal hypoplasia. Polymerase chain reaction for 16 loci in the middle of Xp showed that the brothers of family A had a small Xp deletion between DXS7182 and DXS1022, and that the patient of family B had a tiny Xp deletion between DXS319 and DXS1022. Microsatellite analysis for tetranucleotide repeats in the promoter region of the DAX-1 gene and Southern blotting for DAX-1 and DXS28 showed that the sister and the mother of family A were heterozygous for the interstitial deletion. X inactivation analysis for the methylation status of the AR gene and the HPRT gene indicated that the normal X and the deleted X chromosome underwent random X inactivation in both the sister and the mother. The results imply that an MRX gene subject to X inactivation is present in a roughly 4 Mb region between DXS7182 and DAX-1, and that reduced expression of the normal MRX gene caused by random X inactivation results in MR in carrier females.

Child↗

[Severe male infertility. Genetic investigation and counseling prior to intracytoplasmic sperm injection].

Intracytoplasmatic sperm injection (ICSI) has improved the success rate in treating severe male infertility. The method may now be used with sperm from the epididymis and testis. This article summarizes our knowledge on genetic factors affecting male gamete formation or function. Infertile men with severe impairment of spermatogenesis showed a higher than normal incidence of chromosomal abnormalities and 10-20% had microdeletion, in the Y-chromosome. About 75% of males with congenital bilateral absence of vas deferens (CBAVD) have mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene. In conclusion, we recommend genetic counselling to all couples with a diagnosis of male infertility prior to ICSI. Men with severe oligozoospermia or non-obstructive azoospermia should have karyotype analysis performed and with establishment of diagnostic tools to reveal Y-chromosome deletions, this should be offered to the same group of men. Men with obstructive azoospermia and congenital albilateral absence of vas deferens as well as their wives should be screened for cystic fibrosis mutations.

Chromosome Aberrations↗

Congenital hypertrichosis, osteochondrodysplasia, and cardiomegaly: Cantú syndrome.

Cantú syndrome (hypertrichosis, osteochondrodysplasia, cardiomegaly) is a rare condition, previously reported in 13 patients. We report on two additional patients with this disorder. One of the patients had pulmonary hypertension of unknown cause which was responsive to steroid therapy. She also had unusual, deep plantar creases, not reported previously in Cantú syndrome. Autosomal recessive inheritance has been suggested previously on the basis of sib recurrence in one family and consanguinity in another. We have performed a segregation analysis based on all reported families to date; the data indicate autosomal recessive inheritance is unlikely. A new dominant mutation or microdeletion syndrome are more likely possibilities, sib recurrence possibly representing gonadal mosaicism.

Cardiomegaly↗

[Etiology and treatment of sterility due to azoospermia].

Azoospermia can be classified according to the serum level of FSH into obstructive (OA) or non-obstructive (NOA) azoospermia. It can also be due to a lack of gonadotrophins. In the latter case the administration of FSH and HCG can normalize the sperm production. In the other cases ICSI must be performed. In OA sperm can be retrieved using percutaneous epididymal aspiration or testicular fine needle aspiration in case of failure of vasovasostomy or epididymovasostomy. In NOA or spermatogenic arrest, focal spermatogenesis can be observed in 40 to 50% of cases using repeated testis biopsies, allowing to perform ICSI. Although the risk of malformation in children born after ICSI is not increased there is an increased risk to transmit genetic abnormalities in case of NOA (such as the rate of sex chromosome, or microdeletions of the Y chromosome) and in case of congenital OA (mutations of the cystic fibrosis gene).

Chorionic Gonadotropin↗

Familial cryptic translocation between chromosomes 2qter and 8qter: further delineation of the Albright hereditary osteodystrophy-like phenotype.

Recently five patients with an Albright hereditary osteodystrophy (AHO)-like phenotype were reported to have a subtelomeric deletion of the long arm of chromosome 2. These patients showed a striking resemblance to a number of patients from a large pedigree known to us for a long time. After molecular confirmation of a subtelomeric deletion in one patient, FISH analysis was used and a cryptic translocation between the long arms of chromosomes 2 and 8, t(2;8)(q37.3;q24.3), was detected. Remarkably, five proven and 10 probable cases with a 2qter deletion were found in the family, but none with an 8qter deletion. This was not explained by increased fetal loss. The major clinical characteristics of terminal 2q deletion are a short, stocky build, round face, sparse hair, deeply set eyes, bulbous nose, thin vermilion border, brachymetaphalangism, seizures, and developmental delay. A specific behavioural phenotype consisting of periods of hyperkinesia and aggression can develop with age. The overall phenotype is sufficiently characteristic to allow clinical recognition. The cytogenetic and molecular studies did not narrow down the common deleted region. Both testing of additional 2q markers and characterisation of other AHO-like patients with 2q37 microdeletions may help to define the candidate gene region.

Adolescent↗