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PubMed2002

Relationship between microdeletion on Y chromosome and patients with idiopathic azoospermia and severe oligozoospermia in the Chinese.

OBJECTIVES: To evaluate the relationship between microdeletion or mutation on the Y chromosome and Chinese patients with idiopathic azoospermia and severe oligozoospermia and to establish a molecular detection method. METHODS: Microdeletion or mutation detection at the AZFa (sY84 and USP9Y), AZFb, AZFc/DAZ and SRY regions of the Y chromosome. Seventy-three azoospermia and 28 severe oligozoospermia patients were evaluated using PCR and PCR-SSCP techniques. RESULTS: Twelve of 101 patients (12%) with the AZFc/DAZ microdeletion were found, including 8 with azoospermia (11%) and 4 with severe oligozoospermia (14.3%), and 1 patient had a AZFb and AZFc/DAZ double deletion. No deletions in the AZFa or SRY regions were found. No deletions in AZFa, AZFb, AZFc/DAZ or SRY regions were found in 60 normal men who had produced one or more children. CONCLUSIONS: Microdeletion on the Y chromosome, especially at its AZFc/DAZ regions, may be a major cause of azoospermia and severe oligozoospermia leading to male infertility in China. It is recommended that patients have genetic counseling and microdeletion detection on the Y chromosome before intracytoplasmic sperm injection.

Chromosome Deletion↗

PubMed2004

[Detecting microdeletions of the Y chromosome in patients with high follicle-stimulating hormone azoospermia].

OBJECTIVE: To explore the relationship between the patients' high follicle-stimulating hormone (FSH) azoospermia and microdeletions in Y chromosome. METHODS: Eleven sequence tagged sites (STSs) in Yq were detected by PCR in 16 male patients' high FSH azoospermia. RESULTS: Microdeletions were observed in 6 of 16 male patients and the deletion rate was 37.5%(6/16). Five types of microdeletions were detected: AZFc(SY152), AZFc (SY152+SY254)+AZFd (SY153), AZFc (SY152+SY254+SY255)+AZFd (SY153), AZFc (SY152+SY158+SY255)+AZFd (SY153),and AZFb (SY130)+AZFc (SY158+SY254+SY255)+AZFd (SY153) respectively. CONCLUSION: Microdeletion of Y chromosome was one of the important reasons of the patients' high FSH azoospermia. Before the application of assisted-reproductive technology (ART) to the patients, it is necessary to detect the microdeletions, especially AZFc and AZFd.

Azoospermia↗

PubMed2005

Screening for Y chromosome microdeletions in idiopathic and nonidiopathic infertile men with varicocele and cryptorchidism.

BACKGROUND: Cytogenetic and molecular studies of azoospermic and oligozoospermic males have suggested the presence of azoospermia factors (AZF) in the Y chromosome. Deletion in AZF regions has been reported to disrupt spermatogenesis and cause infertility. Several candidate genes responsible for spermatogenesis have been identified in this region and some of them are thought to be functional in human spermatogenesis. And we reported clinical and molecular studies of Y chromosome microdeletions in Chinese. This study aimed at assessing the frequency of microdeletions in Chinese men with idiopathic and nonidiopathic infertility problems and dicussing the clinical significance of the AZF region. METHODS: In this study, we screened 143 infertile men (62 with idiopathic infertilitas and 81 with nonidiopathic infertilitas), in whom karyotype, sperm count, hormonal parameters and fine needle aspiration cytology were evaluated. Genomic DNA was extracted from the peripheral leukocytes. Molecular analysis was performed by two multiplex polymerase chain reactions (PCR) using a set of a sequence tagged sites (STS) from 3 different regions of the Y chromosome: AZFa (sY84, sY86), AZFb (sY127, sY134), AZFc (sY254, sY255). RESULTS: Nineteen point four percent of idiopathic males (12/62, 19.4%) had microdeletions of either the AZFa, AZFb, AZFc or AZFb + c region. Significantly, a high frequency of microdeletions (9/81, 11.1%) was found in nonidiopathic patients with varicocele and cryptorchidism. No deletions were found in healthy fertile men. There were no significant differences in the localization and extent of deletions between idiopathic and nonidiopathic patients. CONCLUSIONS: The knowledge of the presence of these deletions in idiopathic and nonidiopathic cases is important to understand the prognosis, better management and counsel these patients accordingly. Furthermore, a more extended screening for Y chromosome microdeletions in idiopathic and nonidiopathic men, particularly candidates for intracytoplasmic sperm injection, is recommended.

Chromosome Deletion↗

PubMed1998

[Analysis of a microdeletion in the AZF gene region in azoospermic patients: from research to molecular biology laboratory routine].

Microdeletions in AZF (Azoospermia Factor) region of the Y Chromosome have been recently described in azoospermic or oligozoospermic men. A Y chromosome molecular analysis was performed in peripheral blood DNA obtained from 16 azoospermic patients. Microdeletions within the interval 6 of the long arm of chromosome Y were analysed using the PCR (Polimerase Chain Reaction) technique. The presence of the DAZ (SY255) sequence was tested in 6 patients, while the remaining 10 patients were analysed for 6 different loci mapped to AZFb and AZFc regions. Microdeletion was detected in one azoospermic patient in the YRRM2 sequence. This result supports the finding of microdeletions not involving the DAZ sequence and suggests that routine investigation of azoospermic patients for microdeletions spanning the interval 6 region of y chromosome is also required.

DNA↗

PubMed1998

[Search for microdeletions in the long arm of chromosome Y in 48 infertile men].

About 30% of infertilities are from male origin. They appear in some cases de novo and considered idiopathic. The aim of our work is to evaluate, in these cases, the Y chromosome long arm microdeletion prevalence within the AZF a, b and c regions by molecular biology technics. Were excluded from our study, azoo-oligospermia from hereditary, endocrine, obstructive origins or with a constitutional cytogenetic abnormality. 48 infertile men with a spermogram-proven azoo-oligospermia were studied. Among them, 30 were idiopathics, 8 out of them exhibited a genital infection past history or biological abnormalities suggesting partial obtruction of the genito-urinary tractus. 8 cases of varicocela and 10 of cryptorchidia were also studied. Peripheral blood DNA was extracted from each patient, then amplified by multiplex PCR with STS genomic markers from the 3 Y chromosome AZF zones. PCR products were then analysed on agarose gels. Considering the difficulty to affirm the absence of a signal in molecular biology, each suspicion of deletion was checked by multiplex PCR complication with the SRY marker. 5 Y chromosome long arm microdeletions were diagnosed among our 48 patients. All of them included the AZFc zone and the intragenic DAZ gene markers. Moreover a larger Y chromosome deletion encompassing the 3 AZF zones was diagnosed, and confirmed by the cytogenetic analysis. All the Y chromosome microdeletions were observed in the 22 truly idiopathic azoo/oligospermia, corresponding to a proportion of 22.7% which falls to 10.4% considering the whole population of 48 studied people (closer to the published data). The relatively high proportion of microdeletions found in our series, underlines the need of a strict patient selection to avoid unnecessary search for long arm Y chromosome microdeletions.

Chromosome Deletion↗

PubMed2026

Case Report: Early infantile drug-resistant epilepsy and gastrointestinal dysmotility associated with a de novo GNAO1 variant and a 16p13.11 microdeletion.

BACKGROUND: The GNAO1 gene is located on the long arm of chromosome 16 (16q13) and is associated with Developmental and Epileptic Encephalopathy 17. It encodes a protein involved in regulating various neurotransmitters and neuronal growth and development. The 16p13.11 microdeletion is a genomic deletion in the p13.11 region of the short arm of chromosome 16, previously reported to predispose individuals to neurodevelopmental disorders. These two regions do not overlap on the chromosome, and the 16p13.11 microdeletion does not involve the GNAO1 gene locus. CASE PRESENTATION: We reports a 1-month-old infant presenting with concurrent GNAO1 (p. G203R) gene variation and a 16p13.11 microdeletion. The patient initially presented with recurrent abdominal distension in the neonatal period, which gradually progressed to include focal seizures and intractable epileptic spasms. Interictal EEG showed multifocal discharges and burst-suppression patterns. Brain MRI revealed no abnormalities. A full gastrointestinal series suggested intestinal obstruction and gastro-esophageal reflux. Improved whole-exome sequencing identified: 1) A single nucleotide variantion: GNAO1, NM_020988.3:exon6: c.607G > A (p.Gly203Arg). 2) A copy number variation: A pathogenic 1.453 Mb deletion in the 16p13.11 region. CONCLUSIONS: We describe the developmental trajectory of an infant with overlapping features of gastrointestinal symptoms and drug-resistant epilepsy, carrying a GNAO1 variant and a 16p13.11 microdeletion. This case provides insights into the contribution of both single nucleotide variant and copy number variant to the phenotype.

16p13.11 microdeletion↗

PubMed2006

Microdeletion and microduplication 22q11.2 screening in 295 patients with clinical features of DiGeorge/Velocardiofacial syndrome.

The 22q11.2 region is susceptible to chromosomal rearrangements, leading to various types of congenital malformation and mental retardation. The most common anomaly is 22q11.2 microdeletion, associated with DiGeorge/Velocardiofacial syndrome (DG/VCFS). Recently the microduplication 22q11.2 syndrome has been identified. Some clinical features in patients with this new chromosomal disorder present a substantial overlap with DG/VCFS. The aim of this hospital-based study was to evaluate the incidence of deletions and duplications on 22q11.2 in patients with DG/VCFS features. We investigated a group of 295 patients with widely variable manifestations associated with DG/VCFS. Along with the clinical diagnoses different anomalies were noted such as conotruncal cardiac anomaly, velopharyngeal insufficiency, characteristic facial dysmorphic features, language impairment, developmental delay/learning difficulties, and immunologic anomalies or thymic hypoplasia. Laboratory studies included conventional cytogenetic and FISH testing. Metaphase and interphase cells were analyzed for the presence of 22q11.2 microdeletion or microduplication. There were 12 patients who carried 22q11.2 microdeletion and no microduplication in the region was identified. Other chromosomal anomalies were reported in five patients with an overlapped DG/VCFS phenotype. All patients with 22q11.2 microdeletion showed a characteristic phenotype of DG/VCFS. We did not identify 22q11.2 microduplication, suggesting that this is a rare event in patients with DG/VCFS features.

Adolescent↗

PubMedDate not supplied

Chromosomal abnormalities and y chromosome microdeletions in infertile men with varicocele and idiopathic infertility of South Indian origin.

Various factors cause spermatogenesis arrest in men and, in a large number of cases, the underlying reason still remains unknown. Little attention is paid to determining the genetic defects of varicocele-related infertility. The objective of our present study was to investigate the chromosomal abnormalities and Y chromosome microdeletions in infertile men of South Indian origin with varicocele and idiopathic infertility. Metaphase chromosomes of 251 infertile men with varicocele and unexplained infertility were analyzed using Giemsa-Trypsin-Giemsa (GTG) banding and fluorescence in situ hybridization (FISH). The microdeletions in 6 genes and 18 sequence-tagged-sites (STS) in the Yq region were screened using polymerase chain reaction (PCR) techniques. Out of 251 infertile men, 57 (22.7%) men were with varicocele, of which 8.77% were azoospermic, 26.31% were severely oligozoospermic, 21.05% were mildly oligozoospermic, and 43.85% were oligoasthenoteratozoospermic (OAT), and 194 (77.29%), with idiopathic infertility, of which 51% were azoospermic, 13.40% were severely oligozoospermic, 19.07% were mildly oligozoospermic, and 16.4% were with OAT. Genetic defects were observed in 38 (15.13%) infertile individuals, including 14 (24.56%) men with varicocele and 24 (12.37%) men with idiopathic infertility. The frequencies of chromosomal defects in varicocele and idiopathic infertility were 19.3% and 8.76%, respectively, whereas Y chromosome microdeletions were 5.26% and 3.60%, respectively. Overall rate of incidence of chromosomal anomalies and microdeletions in 251 infertile men were 11.5% and 3.98%, respectively, indicating a very significant higher association of genetic defects with varicocele than idiopathic male infertility. Our data also demonstrate that, among infertile men with varicocele, severely oligozoospermic and OAT men with varicocele have higher incidences of genetic defects than mildly oligozoospermic and azoospermic men.

Adult↗

PubMed2006

22q11 microdeletion studies in the heart tissue of an abortus involving a familial form of congenital heart disease.

Microdeletion of chromosome 22 is responsible for DiGeorge syndrome, Velo Cardio Facial syndrome, and conotruncal defects. Here, we report on a case of microdeletion 22q11.2 in the heart tissue of a miscarried fetus in a family whose two children had died due to complex congenital heart disease. Fluorescence in situ hybridization (FISH) analysis in the couple revealed that the mother was mosaic for microdeletion of chromosome 22q11.2 in 10% of her peripheral lymphocytes. Prenatal diagnosis was offered to her in her third pregnancy. On routine ultrasonography at 10 weeks, the overall view of the heart was normal. However, before any further tests could be performed, she miscarried at 16 weeks. FISH studies on the heart tissue of the abortus revealed 22q11.2 microdeletion with two different cell lines. This suggests the importance of performing FISH studies when there is a history of congenital heart disease, even though ultrasonography shows a normal view of the heart.

Aborted Fetus↗

PubMed2003

Molecular screening for Yq microdeletion in men with idiopathic oligozoospermia and azoospermia.

Infertility affects 15% couples attempting pregnancy and in 40-50% of these cases the male partner has qualitative or quantitative abnormalities of sperm production. Microdeletions in the azoospermia factor (AZF) region on the long arm of the Y chromosome are known to be associated with spermatogenic failure and have been used to define three regions on Yq (AZFa, AZFb and AZFc) which are critical for spermatogenesis and are recurrently deleted in infertile males. Semen analysis was carried out on one hundred and twenty five infertile males with oligozoospermia and azoospermia. Cytogenetic analysis was done for all the cases and in all cytogenetically normal cases (n = 83) microdeletion analysis was carried out on DNA extracted from peripheral blood using PCR. The sequence tagged sites (STS) primers sY84, sY86 (AZFa); sY127, sY134 (AZFb); sY254, sY255 (AZFc) were used for each case. Eight of the eighty three cases (9.63%) showed deletion of at least one of the STS markers. Correlation of phenotype with microdeletion was done in each case to determine any phenotype association with deletion of particular AZF locus. Based on the present study, the frequency of microdeletion in the Indian population is 9.63%. This study emphasizes the need for PCR analysis for determining genetic aetiology in cases with idiopathic severe testiculopathy.

Adult↗

PubMed2003

Absence of microdeletions in the azoospermia-factor region of the Y-chromosome in Viennese men seeking assisted reproduction.

PURPOSE: The azoospermia-factor region of the Y-chromosome is essential for spermatogenesis in humans. In the literature, a wide range is given for the frequency of microdeletions in this region. The purpose of this study was to evaluate our own population of patients. METHODS: During a two-year period at Vienna Medical School, all male patients (n = 383) seeking assisted reproduction were screened for microdeletions. Thirty-three men had azoospermia and 154 severe oligozoospermia. Genomic DNA was prepared from peripheral lymphocytes and polymerase chain reaction analysis of the azoospermia-factor region was performed using the Promega kit. RESULTS: No case tested positive for azoospermia-factor microdeletions. In all cases amplification of 18 non-polymorphic sequence tagged sites was obtained. CONCLUSIONS: Y-chromosome microdeletions do not seem to be an important factor for male infertility in our patients. This suggests that screening should be restricted to men with azoospermia or severe oligozoospermia only.

Chromosome Deletion↗

PubMedDate not supplied

Monozygotic twins with chromosome 22q11 microdeletion and discordant phenotypes in cardiovascular patterning.

Monozygotic twins with chromosome 22q11 microdeletions offer an ideal situation to observe the association of microdeletion and disrupted cardiovascular patterning. We report monozygotic twins concordant for 22q11.2 microdeletion but discordant for cardiovascular patterning. Both twins showed identical intracardiac defects including tetralogy of Fallot with pulmonary atresia. Nevertheless, their great vessel patternings were variable. These twins show that the mispatterning of the great vessels may not correlate with intracardiac morphogenesis. The discordant development of the great vessels, especially in the pulmonary vascular system, has clinical significance for prognosis. The phenotypic variability of cardiovascular anomalies seen in 22q11 microdeletion cannot be explained on the basis of genotypic difference.

Abnormalities, Multiple↗

PubMed2006

Screening for Y microdeletions in men with testicular cancer and undescended testis.

PURPOSE: To investigate a possible association between testicular cancer or undescended testis and Y microdeletions. METHODS: It was designed as a retrospective clinical study. A total of 225 men with testicular cancer or undescended testis were included to study. Fertile men (n = 200) were investigated as a control. Genomic DNA, which was extracted from blood samples were investigated with a fluorescent multiplex PCR protocol for screening for Y microdeletions. RESULTS: A single STS missing was found in eight men; one from the control group (sY153), seven from the patients group. The positive cases showed a single STS missing of marker sY153 and sY139 in testicular cancer (6/185) and undescended testis (1/40) patients, respectively. CONCLUSIONS: Since no contiguous, real Y microdeletions were found in the study population, it seems that Y microdeletions are not a likely common etiological cause of poor spermatogenesis in testicular cancer and undescended testis. However, it remains to be determined whether men having a single STS missing have a risk of developing testis cancer or having undescended testis.

Adult↗

PubMed1996

[Microdeletion of the chromosome 22q11 in children: apropos of a series of 49 patients].

UNLABELLED: Most of the children with Di George syndrome and 60% of patients with velocardiofacial syndrome exhibit a microdeletion within chromosome 22q11. The phenotypic expression of this chromosomal abnormality is highly variable. PATIENTS: Forty-nine children, 0 to 15 years of age, were demonstrated as carriers of a 22q11 microdeletion. The main referral diagnoses were: Di George syndrome (19 cases), velocardiofacial syndrome (14 cases); congenital heart defect with dysmorphism (9 cases); hypoparathyroidism (2 cases). The microdeletion was detected by fluorescent in situ hybridization with probes specific of the 22q11 region. RESULTS: Facial dysmorphism was the only constant feature. A congenital heart defect was present in 84% of cases. Significant hypocalcemia was documented in 51% of cases and thymic hypo or agenesis in 83%. Significant immune deficiency was documented in nine cases. The most frequent associated defects were urinary tract malformations (8 cases). A cleft palate was present in height enfants but velopharyngeal insufficiency was almost constant. Two-thirds of children had psychomotor delay, and five children exhibited behavioral problems. Of the 35 couples of parents tested, eight mothers were found to be carriers of the deletion. CONCLUSION: For the pediatrician, it is essential to know the variability of the clinical picture. The long-term prognosis is conditioned by the possibility of mental retardation and learning disabilities. Parents should be tested for the presence of the deletion. The occurrence of the microdeletion in asymptomatic relatives raises difficult problems in genetic counselling.

Child↗

PubMed1999

Absence of microdeletions in the Y chromosome in patients with a history of cryptorchidism and azoospermia or oligospermia.

OBJECTIVE: To determine if cryptorchidism is associated with microdeletions of interval 6 of the Y chromosome, we evaluated this locus in men with a history of cryptorchidism with and without azoospermia or oligospermia and in a control group. DESIGN: Clinical study. SETTING: Academic research environment. PATIENT(S): Men in whom surgical treatment of cryptorchidism had been performed in childhood and healthy control male subjects. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Genotyping of interval 6 of the Y chromosome. RESULT(S): Analysis of semen obtained from men treated for cryptorchidism in childhood showed azoospermia or oligospermia in 14 of 38 (37%) men. No microdeletions were identified with polymerase chain reaction amplification of 17 distinct sequence tagged sites located on the long arm of the Y chromosome and the sex determining region on Y (SRY) gene. CONCLUSION(S): Microdeletions of interval 6 of the Y chromosome were not detected in either the formerly cryptorchid or in the healthy subjects. Although we cannot exclude the possibility of point mutations, we conclude that cryptorchidism or cryptorchidism associated with azoospermia or oligospermia is not due to microdeletions involving interval 6 of the Y chromosome.

Cryptorchidism↗

PubMed2003

A new approach for screening for Y microdeletions: capillary electrophoresis combined with fluorescent multiplex PCR.

PURPOSE: To apply capillary electrophoresis for rapid screening for Y microdeletions METHODS: A set of 25 specific sequence tagged sites that cover the azoospermia factor a, b, and c regions of the Y chromosome was amplified in 5 fluorescent multiplex sets each including 5 primer pairs. One of the primers of each pair was labeled with a fluorescent tag attached to the 5'-end. After PCR amplification, analysis of the obtained PCR products was performed using capillary electrophoresis (ABI Prism 3100 Genetic Analyzer). The method was employed to determine Y microdeletions in azoospermic (n = 49) and severe oligozoospermic (n = 149) men. RESULTS: The number of PCR cycle (from 45 to 30) and the amount of DNA template (20-fold) used in fluorescent multiplex PCR were reduced because of the high sensitivity of capillary electrophoresis. Approximately 1000 multiplex PCR sets from 198 patients were analyzed simultaneously within 50 h. Y microdeletions were found in 3 out of the 198 azoospermic or severe oligozoospermic men. CONCLUSIONS: Application of capillary electrophoresis for detection of PCR products provides a semiautomated, high throughput method for rapid screening for microdeletions on the Y chromosome.

Chromosome Deletion↗

PubMed2005

Childhood overgrowth in patients with common NF1 microdeletions.

While growth retardation and short stature are well-known features of patients with classical neurofibromatosis type 1 (NF1), we found advanced height growth and accelerated carpal bone age in patients with an NF1 microdeletion. Our analysis is based on growth data of 21 patients with common 1.4/1.2 Mb microdeletions, including three patients with a Weaver-like appearance. Overgrowth was most evident in preschool children (2-6 years, n=10, P=0.02). We conclude that childhood overgrowth is part of the phenotypic spectrum in patients with the common 1.4/1.2 Mb NF1 microdeletions and assume that the chromosomal region comprised by the microdeletions contains a gene whose haploinsufficiency causes overgrowth.

Adolescent↗

PubMedDate not supplied

Xp22.3 microdeletion in a 19-year-old girl with clinical features of MLS syndrome.

We describe a 19-year-old girl who has clinical features of microphthalmia with linear skin defects (MLS) syndrome caused by a microdeletion of Xp22.3. In addition to the classical ocular abnormalities and linear skin defects she has other features not previously described. She was previously reported in this journal in 1990 as poikiloderma congenitale, but her true diagnosis of an Xp22.3 microdeletion was clarified when fluorescent in situ hybridization (FISH) analysis indicated that one of her X chromosomes had a microdeletion including the KAL gene. We describe this patient with an Xp22.3 microdeletion to heighten awareness among dermatologists of this syndrome and to underscore the difficulties in diagnosing MLS syndrome.

Abnormalities, Multiple↗