Qiu-Yue Wu

Clinical, molecular and cytogenetic analysis of 46, XX testicular disorder of sex development with SRY-positive

BackgroundTo review the possible mechanisms proposed to explain the etiology of 46, XX sex reversal by investigating the clinical characteristics and their relationships with chromosomal karyotype and the SRY(sex-determining region Y)gene.MethodsFive untreated 46, XX patients with SRY-positive were referred for infertility. Clinical data were collected, and Karyotype analysis of G-banding in lymphocytes and Fluorescence in situ hybridization (FISH) were performed. Genomic DNA from peripheral blood of the patients using QIAamp DNA Blood Kits was extracted. The three discrete regions, AZFa, AZFb and AZFc, located on the long arm of the Y chromosome, were performed by multiplex PCRs(Polymerase Chain Reaction) amplification. The set of PCR primers for the diagnosis of microdeletion of the AZFa, AZFb and AZFc region included: sY84, sY86, sY127, sY134, sY254, sY255, SRY and ZFX/ZFY.ResultsOur five patients had a lower body height. Physical examination revealed that their testes were small in volume, soft in texture and normal penis. Semen analyses showed azoospermia. All patients had a higher follicle-stimulating hormone(FSH), Luteinizing Hormone(LH) level, lower free testosterone, testosterone level and normal Estradiol, Prolactin level. Karyotype analysis of all patients confirmed 46, XX karyotype, and FISH analysis showed that SRY gene were positive and translocated to Xp. Molecular analysis revealed that the SRY gene were present, and the AZFa, AZFb and AZFc region were absent.ConclusionsThis study adds cases on the five new 46, XX male individuals with SRY-positive and further verifies the view that the presence of SRY gene and the absence of major regions in Y chromosome should lead to the expectance of a completely masculinised phenotype, abnormal hormone levels and infertility.

A Novel p. Gly630Ser Mutation of COL2A1 in a Chinese Family with Presentations of Legg–Calvé–Perthes Disease or Avascular Necrosis of the Femoral Head

Objective Mutations in the type II collagen gene are associated with certain human disorders, collectively termed type II collagenopathies. They include Legg–Calvé–Perthes disease (LCPD) and avascular necrosis of the femoral head (ANFH). These two diseases are skeletal dysplasias, inherited in an autosomal dominant fashion, characterized by groin pain, dislocation of the hip and diminished joint mobility. Coxa vara and elevation of the greater trochanter of the femur comprise the typical phenotype of LCPD, but do not occur in ANFH. Lack of synthesis of type II collagen and structural defects are responsible for the major clinical outcomes, because collagen is the essential matrix protein of all connective tissues. Type II collagen, encoded by the COL2A1 gene, contains N- and C- terminal regions that are cleaved after secretion into the extracellular matrix, and the core area is composed of a triple helical (Gly–X–Y) domain. If the Gly in this specific region is replaced by other amino acids, the structure of type II collagen will be destroyed. Method Forty-five members of a four-generation family were recruited and investigated. Diagnosis was made by independent orthopedic surgeons and radiologists. A mutation of the COL2A1 gene was detected. Result In our research, we identify a heterozygous mutation (c.1888 G>A, p. Gly630Ser) in exon 29 of COL2A1 in the Gly–X–Y domain, in a Chinese family affected by LCPD and ANFH. Our findings provide significant clues to the phenotype–genotype relationships in these syndromes and may be helpful in clinical diagnosis. Furthermore, these results should assist further studies of the mechanisms underlying collagen diseases. Conclusion Our data add new variants to the repertoire of COL2A1 mutation resulting in related collagenopathies.

Polymorphisms in Protamine 1 and Protamine 2 predict the risk of male infertility: a meta-analysis

Several studies have investigated the association between polymorphisms in protamine 1 and 2 genes and male infertility risk, with inconsistent results to date. This meta-analysis based on the 13 published case-control studies, including 7350 cases and 6167 controls, was performed to further establish the potential association between the 6 common single nucleotide polymorphisms (rs35576928, rs737008, rs35262993, rs2301365, rs1646022, rs2070923) in protamines 1 and 2 and male infertility. The -190C > A (rs2301365) polymorphism was identified as a risk factor for male infertility under all models. Interestingly, rs1646022 and rs737008 polymorphisms exerted protective effects against male sterility in Asian and population-based under some models. No associations between the remaining SNPs and male sterility were observed.

Predictive value of GGN and CAG repeat polymorphisms of androgen receptors in testicular cancer: a meta-analysis

The risk of testicular cancer (TC) is markedly increased in subjects with androgen insensitivity, and previous studies have proposed that GGN and CAG repeats in androgen receptors (AR) could be related to the risk of TC. To evaluate the association between the length of GGN and CAG repeats in AR and TC, a meta-analysis involving 3255 TC cases and 2804 controls was performed. The results suggested that long GGN repeats are associated with an increased risk of TC compared with those < 23 [odds ratio (OR) = 1.22, 95% confidence interval (CI) = 1.05–1.41]; similarly, a subgroup analysis revealed that this association occurred in studies with case sizes > 200, and in the mid-latitude, and seminoma subgroups. The subgroup analysis based on populations, high-latitude, and seminomas/non-seminomas suggested that AR CAG repeat polymorphisms with > 25 and < 21 + > 25 repeats might confer a protective effect to the patients with TC (in the high-latitude subgroup analysis, for > 25 vs. 21–25: OR = 0.54, 95% CI = 0.41–0.70). In contrast, an increased risk of TC was observed for AR CAG repeat polymorphisms with > 25 and < 21 + > 25 repeats in the mid-latitude subgroup (for > 25 vs. 21–25: OR = 1.65, 95% CI = 1.09–2.50). In addition, no associations between the remaining subgroups and male infertility were observed. In short, this meta-analysis suggested that AR GGN and CAG repeat polymorphisms may be involved in the etiology of TC.

Polymorphisms in estrogen receptors predict the risk of male infertility: a meta-analysis

BackgroundEstrogen receptors play an important role in mediating estrogen action on target tissues, and the estrogen is relevant to male infertility. Single nucleotide polymorphisms (SNPs) in estrogen receptors may be associated with the risk of male infertility. A variety of case control studies have been published evaluating this association. However, the accumulated studies have shown inconsistent conclusions.MethodsTo further determine the potential association between the four common SNPs (rs2234693, rs9340799, rs1256049 and rs4986938) in estrogen receptors gene and male infertility, this meta-analysis was performed according to the 10 published case control studies. The odds ratio (OR) and 95% confidence interval (CI) were used to evaluate the strength of the associations.ResultsIt was revealed that the sub-group analysis by the ethnicity, for the rs2234693, a significant association in the comparison of CC vs. TT (OR = 0.61, 95% CI: 0.40-0.93), CT vs. TT (OR = 0.67, 95% CI: 0.49-0.93) and CC + CT vs. TT (OR = 0.66, 95% CI: 0.49-0.89) in the Asian population with male infertility. For rs9340799 polymorphism, increased risks were observed for the comparison of AA vs. GG (OR = 1.75, 95% CI: 1.15-2.68) and AA vs. GA + GG (OR = 1.38, 95% CI: 1.02-1.88). For rs1256049 polymorphism, the comparison of the GA vs. GG (OR = 1.52, 95% CI: 1.00-2.31) and AA + GA vs. GG (OR = 1.74, 95% CI: 1.03-2.94), also increased risks present in Asian and Caucasian population, respectively.ConclusionsThe rs2234693C allele was associated with the decreased risk for male infertility; however, the rs9340799AA genotype and the rs1256049GA genotype were associated with an increased risk for male infertility.

Novel mutations in COL4A3, COL4A4, and COL4A5 in Chinese patients with Alport Syndrome

Alport syndrome (AS) is a clinically and genetically heterogeneous, progressive nephropathy caused by mutations in COL4A3, COL4A4, and COL4A5, which encode type IV collagen. The large sizes of these genes and the absence of mutation hot spots have complicated mutational analysis by routine polymerase chain reaction (PCR)-based approaches. Here, in order to design a rapid and effective method for the genetic diagnosis of AS, we developed a strategy by utilizing targeted capture associated with next-generation sequencing (NGS) to analyze COL4A3, COL4A4, and COL4A5 simultaneously in 20 AS patients. All the coding exons and flanking sequences of COL4A3, COL4A4, and COL4A5 from the probands were captured followed by HiSeq 2500 sequencing. Candidate mutations were validated by classic Sanger sequencing and quantitative (q)PCR. Sixteen patients (16/20, 75%) showed X-linked inheritance, and four patients (4/20, 20%) showed autosomal recessive inheritance. None of the individuals had autosomal-dominant AS. Fifteen novel mutations, 6 known mutations, and 2 novel fragment deletions were detected by targeted capture and NGS. Of these novel mutations, 12, 3, and 2 mutations were detected in COL4A5, COL4A4, and COL4A3, respectively. A comparison of the clinical manifestations caused by different types of mutations in COL4A5 suggested that nonsense mutations and glycine substitution by an acidic amino acid are more severe than the other missense mutations. Pathogenic mutations were detected in 20 patients. These novel mutations can expand the genotypic spectrum of AS. Our results demonstrated that targeted capture and NGS technology are effective in the genetic diagnosis of AS.

Clinical and cytogenomic studies in a case of infertility associated with a nonmosaic dicentric Y chromosome.

In this study, a short stature male with infertility is reported. Semen analysis and serum concentrations of FSH, LH, T and PRL were estimated. Chromosome analysis was performed on lymphocytes obtained from both the male and his parents. Cytogenomic studies were performed by fluorescent in situ hybridisation and the CytoScan™ HD array analysis to detect Y chromosomal rearrangements and copy number mutations. Semen analysis showed severe oligozoospermia. Numerous spermatogenic cells were observed in the semen, and approximately 60% of the cells examined in semen were primary spermatocytes, showing spermatogenic arrest at the primary spermatocyte level. Cytogenomic studies of blood revealed his karyotype which was 46,X,i(Y) (p11.32) (Yqter→Yp11.32::Yp11.32→Yqter).ish (DYZ3++, SRY++, SHOX‐). array (PLCXD1→SHOX) ×1,(SRY →GOLGA2P3Y)×2, (DHRSX→ ASMT, SPRY3 →IL9R)×3. The rearrangement Y chromosome is de novo. This is the first case reported with a nonmosaic 46,X, i (Y) (p11.32), which will be useful to estimate the infertility phenotype–molecular karyotype correlation. Haploinsufficiency of short stature homeobox‐containing gene is primarily responsible for the short stature. Aberrations in pseudoautosomal region 1 on the rearranged Y chromosome may result in the deficiency of X‐Y pairing or recombination, ultimately lead to the spermatogenic failure.

Hyperhomocysteinaemia in rats is associated with erectile dysfunction by impairing endothelial nitric oxide synthase activity

To investigate the effect of hyperhomocysteinaemia (HHCy) on penile erectile function in a rat model, a methionine-rich diet was used in which erectile function, the reproductive system, and nitric oxide synthase were characterized. The intracavernous pressure, apomorphine experiments, measurement of oxidative stress, hematoxylin and eosin staining, immunohistochemistry analysis, reverse transcription-polymerase chain reactions and measurement of endothelial nitric oxide synthase activity were utilized. Our results showed that erections in the middle-dose, high-dose, and interference (INF) groups were significantly lower than the control (P < 0.05). INF group, being fed with vitamins B and folic acid, demonstrated markedly improved penile erections compared with the middle-dose group (P < 0.05). HHCy-induced eNOS and phospho-eNOS protein expression was reduced and the antioxidant effect was markedly impaired. The data of the present data provide evidence that HHCy is a vascular risk factor for erectile dysfunction by impairing cavernosa endothelial nitric oxide synthase activity. Intake of vitamins B can alleviate this abnormality.

A parthenogenetic maternal and double paternal contribution to an ovotesticular disorder of sex development.

BackgroundAn ovotesticular disorder of sex development (OT-DSD) was rarely found in human. The mechanism causing such condition is poorly understood. We hereby reported a 11-year-old child with OT-DSD and a karyotype 46,XX/46,XY, a single maternal and double paternal genetic contribution to the patient.ResultsFluorescence in situ hybridization (FISH), blood grouping, HLA (human leukocyte antigen) haplotyping and a genome-wide scanning of lymphocytes with 398 short tandem repeat microsatellite markers were performed to investigate the origin of the cell lines concerned. ABO typing revealed that two populations of red cells were in the patient, which were group A and group B, both from paternal alleles. HLA haplotyping showed the patient had three haplotypes. Haplotype 1 was inherited from maternity, haplotype 2 and 3 were from paternity. The STR microsatellite analysis showed 25 of the 74 fully informative markers in both parents, three alleles were inherited: one of them was from mother, another two were from father. Seventeen of the thirty-eight paternal markers, the patient inherited two paternal alleles. For 121 informative maternal markers, the patient had a single maternal allele. There were two distinct alleles in locus DXS6810 and DXS1073 on X-chromosome, in which one was from the mother and the other from the father.ConclusionsThe patient was a single maternal and double paternal genetic, which was a type of a parthenogenetic division of a maternal haploid nucleus into two identical nuclei, followed by fertilization by two spermatozoa and fusion of the two zygotes into a single individual at the early embryonic stage. To the best of our knowledge, this is the oldest OT-DSD case of parthenogenetic chimerism. These data provide additional evidence that a parthenogenetic maternal and double paternal contribution causes 46,XX/46,XY OT-DSD.

A novel nonsense mutation of ADAR1 gene in a Chinese patient with dyschromatosis symmetrica hereditaria

A novel nonsense mutation of ADAR1 gene in a Chinese patient with dyschromatosis symmetrica hereditaria Editor Dyschromatosis symmetrica hereditaria (DSH, MIM 127400) is an autosomal dominant pigmentary disorder characterized by the presence of hyperpigmented and hypopigmented macules mostly on the dorsal of the extremities, which first appear in infancy or early adolescence, and last for life. Genetic studies have certified that the mutations in the ADAR1 gene are responsible for the disorder. So far, more than 100 mutations in the ADAR1 gene have been reported that were associated with the disorder. We reported a patient with DSH who carried a heterozygous mutation c.1479 C>G (p.Y493X) in the exon 2 of the ADAR1 gene presented macules around the joints of elbow and knee in addition to the dorsal of the extremities. Combining the novel mutation location with those reported in literatures, we hereby discuss the possible relationship between the genotype and phenotype. The patient in this study showed typical hyperpigmented and hypopigmented macules on the extremities since about 7 years old (Fig. 1a,b) and often felt a little itch. Similar macules on elbow (Fig. 1c) and knee joints (Fig. 1d) appeared when she was 20 years old. For some reasons, the patient refused to take skin biopsy examination. The research adhered to the tenets of The Declaration of Helsinki. The Ethics Committee of Jinling Hospital approved the protocol. The patient gave written informed consent. Genomic DNA was extracted (TIANamp Genomic DNA Kit; Tiangen, nanjing, China) from the whole blood samples of the patient, the patient’s daughter and 100 unrelated controls. All translated exons and flanking intronic sequences of the ADAR1 gene were amplified and sequenced. The sequencing results were compared to the NCBI Reference Sequence (NG _011844). A novel heterozygous mutation c.1479C>G (p.Y493X) (Fig. 2) was identified in the exon 2 of the ADAR1 gene. No same nonsense mutation was found in the patient’s daughter and 100 unrelated controls, which suggested the novel mutation was not a polymorphism. The ADAR1 gene, encoding double-stranded RNA-specific adenosine deaminase, has 15 exons and contains at least six functional domains: two Zalpha (Z-DNA-binding domain in