[The role of the ubiquitin proteasome system and PP2A in spermatogenesis].

The ubiquitin proteasome system (UPS) plays an important role in cell degradation, and is involved in many biological processes such as cell cycle regulation, immune response, DNA damage repair, and signal transduction. It also acts a crucial part in spermatogenesis by selectively degrading proteins and regulating such processes as DNA repair and protamine histone replacement. PP2A, as an essential serine/threonine phosphatase, participates in a variety of life activities. Studies have shown the involvement of UPS in the ubiquitination regulation of PP2A and that of PP2A in several stages of meiosis. This review updates the roles of UPS and PP2A in spermatogenesis.

[Biosafety in andrology laboratories during the outbreak of COVID-19].

The novel coronavirus disease 2019 (COVID-19) broke out in December 2019 and has been rapidly escalating throughout the world. Clinical findings show that the patients with either symptomatic or asymptomatic COVID-19 can be a potential source of infection. Although respiratory droplets and close contact are considered to be the main routes of transmission, there is the possibility of aerosol transmission in a relatively closed environment. The nucleic acid of the novel coronavirus can be detected in nasopharyngeal swabs, sputum and other lower respiratory tract secretions, blood, feces, urine and so on, but whether it exists in the semen has not been confirmed. It is reported that the novel coronavirus may affect the testis that highly expresses angiotensin-converting enzyme 2 (ACE2) and theoretically the semen is a possible carrier of the virus considering the fact that it is discharged from the same channel as the urine. Andrology laboratorians are exposed to most of the specimens above, including semen, and some open operations in the laboratory increase the risk of aerosol generation. Therefore, corresponding protective procedures are necessitated in andrology laboratories to reduce the risk of infection during the outbreak of COVID-19. Based on the knowledge and experience available as regards the pandemic and the characteristics of the work in the andrology laboratory, we summarize some biosafety points for andrology laboratorians to attend to during the outbreak of COVID-19.

[Association of Ureaplasma urealyticum with the types of antisperm antibody in infertile men].

OBJECTIVE: To investigate the prevalence of Ureaplasma urealyticum (UU) infection in infertile men, its influence on routine semen parameters and the distribution of antisperm antibody (AsAb) and its types in infertile patients with UU infection. METHODS: We detected the positive rate of UU infection, semen parameters, and the distribution of AsAb and its types in 662 infertile men and 25 normal fertile male controls followed by comparison of the obtained data between the two groups of subjects. RESULTS: The positive rate of UU infection was significantly higher in the infertile men than in the normal controls (52.87% ï¼»350/662ï¼½ vs 16.00% ï¼»4/25ï¼½, χ2 = 11.68, P <0.05). The semen volume, sperm count, sperm concentration and percentage of progressively motile sperm were remarkably lower in the UU-positive infertile males than in the control group (P <0.05). No statistically significant difference was observed between the UU-positive and UU-negative groups in the positive rates of total AsAb (43.4% vs 36.5%, χ2 = 3.25, P >0.05) and AsAb IgA, IgM and IgG in the seminal plasma, or in the percentages of serum AsAb IgM (16.9% vs 20.5%, χ2 = 1.22, P >0.05) and IgG (32.7% vs 28.9%, χ2 = 0.99, P >0.05) except in that of serum AsAb IgA (23.6% vs 17.0%, χ2 = 4.03, P <0.05). CONCLUSIONS: The UU infection rate is high in infertile males, which decreases the semen volume, total sperm count, motile sperm concentration and percentage of progressively motile sperm and increases the positive rate of serum AsAb IgA.

[Impact of Mycoplasma and Chlamydia infections on male reproduction].

Infertility can be attributed to reproductive tract infections (RTI), most commonly nongonococcal urethritis, mainly including Mycoplasma and Chlamydia infections, which may directly or indirectly damage spermatozoa and spermatogenic cells. In addition, a series of immune responses caused by such infections are also associated with male infertility. Methods for the clinical detection of these microbial infections are being constantly improved for more specific and precise control over the impact of Mycoplasma and Chlamydia infections on male fertility.

[Sperm chromatin structure assay versus sperm chromatin dispersion test in detecting sperm DNA integrity and correlation of sperm DNA fragmentation with semen parameters].

OBJECTIVE: Sperm DNA fragmentation (SDF) is widely used to predict male infertility and the methods of detecting SDF are varied. This study aimed to compare two methods of SDF detection and investigate the correlation between SDF and sperm quality. METHODS: Using sperm chromatin structure assay (SCSA) and sperm chromatin dispersion test (SCD), we detected SDF in 108 semen samples collected in the Center of Reproduction and Genetics of Suzhou Municipal Hospital. We compared the results of the two methods and analyzed the correlations of SDF routine semen parameters, sperm morphology and the age of the patients. RESULTS: A significant consistency was found in the SDF index (DFI) between the two methods (P<0.01). The DFI was correlated negatively with sperm motility, the percentage of progressively motile sperm, and that of morphologically normal sperm (P <0.01), but positively with the teratozoospermia index (P <0.01 in SCSA and P <0.05 in SCD). The DFI measured by SCSA showed a significantly positive correlation with the patients' age (P <0.01), but not that obtained by SCD. CONCLUSIONS: The results of both SCSA and SCD play an important role in predicting sperm quality. As a clinical index, the DFI has a predictive value for male infertility. However, the results of different detecting methods vary widely, which calls for further studies on their standardization.

[Ultrastructural observation of morphologically abnormal sperm: Advances in studies and application].

Sperm ultrastructural abnormalities are often associated with sperm motility, the integrity of genetic material, and the fertilization potential. The investigation of sperm ultrastructural abnormalities is based on the evolution of microscopy techniques. In his paper, we review the improvement of the microscopy techniques and the ultrastructure of several specific morphological defects and he apoptotic spermatogenic cells in order to expound the significance of sperm ultrastructural observation in clinical practice. We deem it necessary to analyze the sperm ultrastructure before exploring the pathology and adopting assisted reproductive technology for some special patients with teratozoospermia.

[Reliability and validity of the Chinese version of The Premature Ejaculation Diagnostic Tool].

OBJECTIVE: To translate the English version of The Premature Ejaculation Diagnostic Tool (PEDT) into Chinese, evaluate its reliability and validity, and analyze its feasibility in the diagnosis of premature ejaculation (PE). METHODS: Following the forward-backward translation procedure, we developed the Chinese version of PEDT, which was then revised by andrologists and bilingual linguists. We enrolled subjects with or without PE from 15 urological or andrological clinics in China and obtained the information about their demographic characteristics, PEDT scores, and intra-vaginal ejaculation latency time (IELT). We evaluated the internal consistency of PEDT using Cronbach alpha, was examined its reliability and stability by test-retest analysis, analyzed its correlation with IELT by Spearman correlation analysis, and tested its sensitivity and specificity by receiver operating characteristic ( ROC) analysis. RESULTS: Totally, 570 PE patients (aged [30.66 ± 7.11] years) and 226 non-PE men (aged [33.01 ± 5.41] years) were recruited, with the mean IELT of (1.34 ± 0.54) min in the former and (11.09 ± 7.5) min in the latter group. The Cronbach's alpha of the Chinese version of PEDT was 0.79, and the test-retest correlation coefficient was 0.75 (P < 0.01). The PEDT score was negatively correlated with IELT (Spearman's p = -0.52, P < 0.01). When the cutoff value of PE diagnosis was defined as 7.5, the sensitivity and specificity of PEDT were 0.80 and 0.78, and when as 8.5, they were 0.72 and 0.89, respectively. CONCLUSION: The Chinese version of PEDT was demonstrated to have good internal consistency, reliability, and validity, as well as a high predictability for PE. It can be used as a reliable and convenient tool to screen PE among Chinese men.

46,XX testicular disorder of sexual development with SRY-negative caused by some unidentified mechanisms: a case report and review of the literature.

BACKGROUND: 46,XX testicular disorder of sex development is a rare genetic syndrome, characterized by a complete or partial mismatch between genetic sex and phenotypic sex, which results in infertility because of the absence of the azoospermia factor region in the long arm of Y chromosome. CASE PRESENTATION: We report a case of a 14-year-old male with microorchidism and mild bilateral gynecomastia who referred to our hospital because of abnormal gender characteristics. The patient was treated for congenital scrotal type hypospadias at the age of 4 years. Semen analysis indicated azoospermia by centrifugation of ejaculate. Levels of follicle-stimulating hormone and luteinizing hormone were elevated, while that of testosterone was low and those of estradiol and prolactin were normal. The results of gonadal biopsy showed hyalinization of the seminiferous tubules, but there was no evidence of spermatogenic cells. Karyotype analysis of the patient confirmed 46,XX karyotype and fluorescent in situ hybridization analysis of the sex-determining region Y (SRY) gene was negative. Molecular analysis revealed that the SRY gene and the AZFa, AZFb and AZFc regions were absent. No mutation was detected in the coding region and exon/intron boundaries of the RSPO1, DAX1, SOX9, SOX3, SOX10, ROCK1, and DMRT genes, and no copy number variation in the whole genome sequence was found. CONCLUSION: This study adds a new case of SRY-negative 46,XX testicular disorder of sex development and further verifies the view that the absence of major regions from the Y chromosome leads to an incomplete masculine phenotype, abnormal hormone levels and infertility. To date, the mechanisms for induction of testicular tissue in 46,XX SRY-negative patients remain unknown, although other genetic or environmental factors play a significant role in the regulation of sex determination and differentiation.

[Relationship of sperm morphology with the outcomes of in vitro fertilization and embryo transfer].

OBJECTIVE: To study the application value of normal sperm morphology on the outcomes of classic in vitro fertilization and embryo transfer (IVF-ET). METHODS: This study included 659 infertile couples admitted to our center for IVF-ET. Based on the percentage of morphologically normal sperm (MNS), we divided the patients into groups A (n = 112, MNS < 2%), B (n = 180, MNS > or = 2 - < 4%), C (n = 74, MNS > or = 4 - < 5%), and D (n = 293, MNS > or = 5%), and compared the rates of fertilization, normal fertilization, embryos obtained, biochemical pregnancy, clinical pregnancy, implantation, and live birth among different groups. RESULTS: The mean fertilization rate was significantly higher in groups C (71.90%) and D (72.89%) than in A (57.97%) and B (63.29%) (P < 0.05), with no remarkable differences either between A and B (P > 0.05) or between C and D (P > 0.05). The normal fertilization rate was also significantly higher in group D (57.16%) than in A (46.52%) and B (50.89%) (both P < 0.05) as well as in C (54.67%) than in A (P < 0.05). The rate of embryos obtained, too, was markedly higher in group D (55.62%) than in B (45.75%) (P < 0.05), but none with remarkable difference from other groups (all P > 0.05). There were no statistically significant differences among the four groups in the rates of biochemical pregnancy, clinical pregnancy, implantation, abortion, and live birth (all P > 0.05). CONCLUSION: The rate of MNS had some influence on IVF-ET, and 5% MNS exhibited a higher value than 4% MNS in predicting the outcomes of IVF.

[The value of histopathologic examination of testis tissue from testicular sperm aspiration].

OBJECTIVE: To evaluate histopathologic examination of the testis tissue from testicular sperm aspiration (TESA). METHODS: We analyzed the results of inverted microscopy and histopathologic examination of 96 samples of testis tissue from TESA, and compared the accuracy of the two methods in detecting sperm in the testis tissue. RESULTS: Among the 11 cases in which sperm was found by inverted microscopy, 9 were confirmed by histopathologic examination, and among the 57 cases in which sperm was not detected by inverted microscopy, 11 (19.3%) were found with sperm by histopathologic examination. Histopathologically, the cases in which sperm was not found by inverted microscopy included Sertoli-cell-only syndrome (n = 34), maturation arrest (n = 12) and hypospermatogenesis (n = 11). CONCLUSION: Histopathologic examination may reveal sperm in the TESA testis tissue proved to be sperm-absent by microscopy, and thus offer valuable information for a second testicular sperm retrieval.

[Analysis of GJB2 gene and mitochondrial DNA A1555G mutations in 16 families with non-syndromic hearing loss].

OBJECTIVE: To screen for genetic mutations in families featuring non-syndromic hearing loss. METHODS: Sixteen families with non-syndromic hearing loss were interviewed to identify medical histories by a questionnaire. Audiological and neurological examinations were conducted for all families. Coding regions of GJB2 and 12S rRNA genes were amplified and sequenced. RESULTS: Of the 17 patients with sensorineural hearing loss, 3 were homozygous mutation for GJB2 235 delC, 1 was 235 delC heterozygous mutation, 1 was 235 delC+299_300 delAT compound heterozygous mutation, and 6 were 79G>A+341G>A heterozygosis in cis mutation. No 1555A>G mutation of mitochondrial DNA (mtDNA) was found in the 16 families. CONCLUSION: The incidence of mtDNA 12S rRNA 1555A>G mutation in Jiangsu province may be lower than the average across China. Mutations of GJB2 genes may account for as much as 64.7% of non-syndromic hearing loss in this study. Screening for such mutations and genetic counseling may play an important role in the prevention of hereditary hearing loss.

[Susceptibility to prostate cancer in Han Chinese: single nucleotide polymorphism analysis of 1 667 cases].

OBJECTIVE: Prostate cancer (PCa) has the highest incidence among male malignancies in Western industrialized countries and, as a most common malignant disease in urology, its incidence has been increasing in recent years in Chinese men. This study was to investigate the risk loci associated with PCa susceptibility in Han Chinese by analyzing single nucleotide polymorphisms (SNP). METHODS: We collected peripheral blood samples from 1 667 PCa patients and 1 525 healthy men, and detected 40 loci associated with PCa susceptibility by analyzing SNPs using Sequenom technology. RESULTS: Of the 40 known loci, 16 were confirmed to be significantly associated with PCa susceptibility (P < 0.05). The loci 1, 2 and 5 at 8q24, 10q11 and 22q13.2 also contributed to PCa susceptibility in different ethnic groups. CONCLUSION: PCa susceptibility is obviously associated with the risk loci rs1465618, rs721048, rs12621278, rs7679673, rs12653946, rs339331, rs1512268, rs10086908, rs16901979, rs1447295, rs10993994, rs10896449, rs902774, rs9600079, rs11649743 and rs5759167 in Chinese Han population.

[Mutation of the USP26 gene in spermatogenesis dysfunction].

The ubiquitin specific protease 26 (USP26) gene is located at Xq26.2 and present as a single exon on the X chromosome encoding for a protein of 913 amino acids. It belongs to a large family of deubiquitinating enzymes, and is exclusively expressed in the testis. There are conflicting reports on whether mutations in USP26 are associated with male infertility. This article updates the researches on the USP26 gene, its complicated relationship with male spermatogenesis dysfunction, the role of its mutation in male infertility, its geographical or ethnic distribution, and its evolution.

[Sex chromosomes and male infertility].

Male infertility is a worldwide problem, with a variety of causes including genetic factors. Sex chromosomes are particularly interesting, as males only have a single copy of both chromosomes. The Y chromosome is obviously an area of interest in the study of male-factor infertility because it contains many of the genes that are critical for spermatogenesis and the development of male gonads. Y chromosome microdeletions are the most commonly known genetic causes of spermatogenic failure in males. The azoospermia factor (AZF) region is a particular area on the long arm of the Y chromosome, Yq, where microdeletions occur most frequently. Fourteen Y chromosome genes encoding putatively functional proteins and expressed in the human testis are found to be located in one of the three AZF intervals. The exact role of specific AZF genes in spermatogenesis is largely unknown, for each of the most classical Yq deletions removes multiple genes. The importance of the X chromosome in mammalian spermatogenesis is suggested by its enrichment of germ cell-specific genes expressed in spermatogenesis, such as AR, USP26, TAF7L, TEX11, KAL1, AKAP4, and NXF2. Genes on the X chromosome may be under unique evolutionary pressure due to their hemizygous expression in male. The mutations in the single copy X-linked genes, unlike in autosomal genes, would not be masked by a normal allele. Many researches have been conducted on the relationship between spermatogenesis and the genes on the X chromosome, but the involvement of the X chromosome in male infertility remains less understood and deserves further characterization.

[AZF microdeletions on the Y chromosome in infertile Chinese men: a five-year retrospective analysis].

OBJECTIVE: The past few years have seen great progress in the studies of the relationship between AZF microdeletions and male infertility. However, some molecular and clinical concerns are not supported by definitive data. The aim of this study was to investigate the prevalence and types of AZF microdeletions in infertile Chinese men, and the indications for genotype-phenotype correlation. METHODS: We retrospectively analyzed Y chromosome AZF microdeletions among 502 patients with nonobstructive azoospermia and 306 with severe oligozoospermia received in our hospital during the past five years. RESULTS: Microdeletions were detected in 7.80% of the patients (63/808), 9.16% in the men with nonobstructive azoospermia (46/502) and 5.56% in those with severe oligozoospermia (17/306). Complete AZFa and AZFb (P5/Proximal P1) deletions were associated with azoospermia, whereas AZFc deletion with variable spermatogenic phenotypes. A mild decline in sperm concentration was found in one male with partial AZFb deletion. The most frequent deletion was the AZFc b2/b4 subtype (60.32%, 38/63), and 39.47% of the cases (15/38) had sperm in the ejaculate. Of the 63 deletions, only one case of the AZFc b2/b4 type had a sperm concentration of over 2 million sperm/ml. CONCLUSION: AZF microdeletions play a significant role in the diagnosis and evaluation of spermatogenic defects. Larger-scale clinical researches on Y chromosome microdeletions may give us a deeper insight into their mechanism and the genotype-phenotype relationship.

The Efficacy of Fecal Microbiota Transplantation for Children With Tourette Syndrome: A Preliminary Study.

Therapies for Tourette syndrome (TS) are insufficient, and novel therapies are needed. Fecal microbiota transplantation (FMT) has been a potential therapy for several neurological diseases. Here, we report a preliminary study to investigate the effects of FMT on patients with TS. Five patients with TS received a single administration of FMT via endoscopy. Tic symptoms were assessed by Yale Global Tic Severity Scale-Total Tic Score (YGTSS-TTS) and adverse effects were recorded at week 8 following FMT. Lipopolysaccharide (LPS) levels and 14 cytokines levels were measured. The microbiota profile in feces were analyzed by shotgun metagenomics. Four patients (4/5) responded positively to FMT (YGTSS-TTS reduction rate >25%) at week 8 with high safety. The levels of LPS and cytokines varied after FMT. FMT shifted the composition of the gut microbiota in patients close to that of the donor and continuously changed the abundance of Bacteroides coprocola, Dialister succinatiphilus and Bacteroides vulgatus. The restoration of B.coprocola was correlated with the improvement in tic symptoms (Spearman R = -0.900, P = 0.037). In conclusion, FMT was indicated a potential effective and safe alternative for patients with TS. However, larger clinical trials are needed to confirm the influence of microbiota in TS. Trial Registration: chictr.org.cn Identifier: ChiCTR-IIR-17011871, URL: http://www.chictr.org.cn/showproj.aspx?proj=19941.

Effects of Proton Pump Inhibitors on the Gastrointestinal Microbiota in Gastroesophageal Reflux Disease.

Proton pump inhibitors (PPIs) are commonly used to lessen symptoms in patients with gastroesophageal reflux disease (GERD). However, the effects of PPI therapy on the gastrointestinal microbiota in GERD patients remain unclear. We examined the association between the PPI usage and the microbiota present in gastric mucosal and fecal samples from GERD patients and healthy controls (HCs) using 16S rRNA gene sequencing. GERD patients taking PPIs were further divided into short-term and long-term PPI user groups. We showed that PPI administration lowered the relative bacterial diversity of the gastric microbiota in GERD patients. Compared to the non-PPI-user and HC groups, higher abundances of Planococcaceae, Oxalobacteraceae, and Sphingomonadaceae were found in the gastric microbiota from the PPI-user group. In addition, the Methylophilus genus was more highly abundant in the long-term PPI user group than in the short-term PPI-user group. Despite the absence of differences in alpha diversity, there were significant differences in the fecal bacterial composition of between GERD patients taking PPIs and those not taking PPIs. There was a higher abundance of Streptococcaceae, Veillonellaceae, Acidaminococcaceae, Micrococcaceae, and Flavobacteriaceae present in the fecal microbiota from the PPI-user group than those from the non-PPI-user and HC groups. Additionally, a significantly higher abundance of Ruminococcus was found in GERD patients on long-term PPI medication than that on short-term PPI medication. Our study indicates that PPI administration in patients with GERD has a significant effect on the abundance and structure of the gastric mucosal microbiota but only on the composition of the fecal microbiota.

Molecular prenatal diagnosis in 2 pregnancies at risk for spondyloepiphyseal dysplasia congenita.

BACKGROUND: Spondyloepiphyseal dysplasia congenita (SEDC) is an autosomal dominant skeletal dysplasia characterized by short stature, abnormal epiphyses, and flattened vertebral bodies. Secondary prevention of SEDC can be achieved by prenatal diagnosis. Reports of antenatally-diagnosed SEDC fetuses have been very rare and molecular prenatal diagnosis even rarer. We previously reported a familial G504S mutation in the type II collagen (COL2A1) gene resulting in SEDC. In this study, molecular prenatal diagnosis was performed to 2 couples in this family with pregnancies at risk for SEDC. METHODS: Amniotic fluid was sampled by amniocentesis under ultrasound guidance at 19+3 and 18+6 weeks' gestation, respectively. Karyotype and molecular genetic analysis were performed on cultured amniotic fluid cells. Maternal cell contamination was excluded by short tandem repeat (STR) analysis. Direct DNA sequencing and DHPLC were conducted to detect the potential mutation in exon 23 of COL2A1 gene. Both women underwent serial sonograms because they insisted that the molecular diagnosis should be confirmed by another method, although they had been informed that mutation analysis is predictive of the disease. RESULTS: Karyotype of both fetuses was normal and molecular genetic analysis revealed that fetus 1 carried a G504S mutation in exon 23, while fetus 2 was normal. In case 1, femur length of the fetus was markedly below the 5th centile at 23 weeks' gestation, which confirms the accuracy of molecular diagnosis. A medical termination was carried out at 27+5 weeks' gestation and a male fetus with a relatively large head and short limbs was delivered. The fetal radiograph demonstrated a number of features, including generalised platyspondyly, absent ossification of the vertebral bodies in the cervical region and significant shortening of the long bones. The diagnosis of SEDC was thus confirmed clinically. Ultrasound monitoring of fetus 2 showed that its femur length was normal for gestational age at repeated scans, which was consistent with the molecular diagnosis. CONCLUSIONS: Molecular analysis allows early and accurate prenatal diagnosis for SEDC once mutation is known in a family. However, considering the poor genotype/phenotype correlation in many cases of SEDC, the combination of ultrasound as well as molecular genetic approach might be needed.

A novel RNA-splicing mutation in COL1A1 gene causing osteogenesis imperfecta type I in a Chinese family.

BACKGROUND: Osteogenesis imperfecta (OI), also known as brittle bone disease, is a rare heterogeneous group of inherited disorders characterized by low bone mass and increased bone fragility. The four major clinical criteria for diagnosis of OI are osteoporosis with abnormal fragility of the skeleton, blue sclera, dentinogenesis imperfecta, and premature otosclerosis. The presence of two of these abnormalities confirms the diagnosis. More than 90% patients have autosomal dominant mutations in one of the two genes, COL1A1 and COL1A2, that encode the alpha chains of type I collagen. While the diagnosis of OI is still based on clinical and radiological grounds, there is a growing demand for the molecular characterization of causative mutations. Although there have been several studies on the mutational spectra of COL1A1 and/or COL1A2 in Western populations, very few cases have been reported from Asia. The purpose of this study is to report two patients with OI type I in a Chinese family, who had a novel RNA-splicing mutation in COL1A1 gene and describe the molecular, radiological and clinical findings. METHODS: The proband, (case II-5), a 32-y-old Chinese male, and his 7-y-old daughter were diagnosed as OI type I according to their clinical and radiological features. Genomic DNA was extracted from their blood samples and all promoters, exons and exon/intron boundaries of COL1A1 and COL1A2 genes were sequenced. Polymerase chain reaction sequence-specific primers (PCR-SSP) was used to confirm patients' heterozygous state. RESULTS: Direct DNA sequencing analysis of COL1A1 gene revealed a splicing mutation (c.1875+1G>A, also as IVS 27+1G>A) that converted the 5' end of intron 27 from GT to AT. This mutation was found in both 2 affected individuals but 9 unaffected relatives and the 50 controls were not observed, which was consistent with the clinical diagnosis. This mutation (c.1875+1G>A) appeared to be novel, which is neither reported in literature nor registered in the Database of Collagen Mutations. The heterozygous states of patients' intron 27 were confirmed by PCR-SSP. CONCLUSION: We identify a novel RNA-splicing mutation (c.1875+1G>A) in COL1A1 gene resulting in OI type I in a Chinese family. The detailed molecular and clinical features will be useful for extending the evidence for genetic and phenotypic heterogeneity in OI and exploring the phenotype-genotype correlations in OI.

Rapid molecular prenatal diagnosis of spondyloepiphyseal dysplasia congenita by PCR-SSP assay.

Heterozygous mutations of COL2A1 gene are responsible for type II collagenopathies. The common skeletal phenotypes include achondrogenesis type II, hypochondrogenesis, Stickler dysplasia, Kniest dysplasia, late onset spondyloepiphyseal dysplasia, and spondyloepiphyseal dysplasia congenita (SEDC). Prevention of SEDC can be achieved by prenatal diagnosis. This study reports the first rapid molecular prenatal diagnosis of SEDC performed in China by polymerase chain reaction sequence-specific primer (PCR-SSP) analysis. The pregnant woman we previously reported with SEDC carried the G to A substitution at nucleotide 1510 in exon 23 of COL2A1 gene, which caused a change from glycine to serine at codon 504 (G504S). By the time the woman got pregnant again, she had terminated two pregnancies and still had no child. In the first pregnancy, the molecular mutation of the family was not yet identified, and therefore prenatal diagnosis was unable to be performed by DNA analysis. In the second pregnancy, G504S mutation was found from fetal DNA. At the time of her third pregnancy, the woman and her husband became extremely worried about the potential SEDC for the fetus. For this reason, a quick and reliable molecular prenatal diagnosis of SEDC was performed by a PCR-SSP on an amniocyte sample collected at the 14th week of pregnancy. No mutation of the fetal DNA was identified. The result was obtained within 24 h after the sample was collected. The technique could be applied in confirmatory diagnosis and prenatal diagnosis for the affected family.