Copy-number analysis of Y-linked loci in young men with non-obstructive azoospermia: Implications for the rarity of early onset mosaic loss of chromosome Y.

PURPOSE: Mosaic loss of chromosome Y (mLOY) is a common feature in elderly men. If mLOY can also occur in young men, it may lead to spermatogenic failure due to loss of spermatogenic genes. Indeed, previous studies detected the 45,X/46,XY karyotype in a few young men with spermatogenic failure. The present study aimed to clarify the frequency of cryptic mLOY in reproductive-aged men with spermatogenic failure. METHODS: We studied 198 men at ages 24-55 years who presented with etiology-unknown non-obstructive azoospermia. Prior this study, these patients underwent G-banding analysis for 20 leukocytes and were found to have 46,XY karyotype. We analyzed copy numbers of chromosome Y in blood cells by using semi-quantitative multiplex PCR for AMELY/AMELX, array-based comparative genomic hybridization (CGH) for the AMELY locus, and droplet digital PCR for SRY, USP9Y, and UTY. RESULTS: Multiplex PCR showed borderline low AMELY/AMELX ratios in three patients. However, for the three patients, CGH excluded deletion of the AMELY locus, and droplet digital PCR suggested preserved copy numbers of all tested loci. CONCLUSION: This study highlights the rarity of leukocyte mLOY in reproductive-aged men with spermatogenic failure. In addition, our data imply that standard karyotyping is sufficient to screen early onset mLOY.

Sex chromosomes-linked single-gene disorders involved in human infertility.

Human infertility is a healthcare problem that has a worldwide impact. Genetic causes of human infertility include chromosomal aneuploidies and rearrangements and single-gene defects. The sex chromosomes (X and Y) are critical players in human fertility since they contain several genes essential for sex determination and reproductive traits for both men and women. This paper provides a review of the most common sex chromosomes-linked single-gene disorders involved in human infertility and their corresponding phenotypes. In addition to the Y-linked SRY gene, which mutations may cause XY gonadal dysgenesis and sex reversal, the deletions of genes present in AZF regions of the Y chromosome (DAZ, RBMY, DBY and USP9Y genes) are implicated in varying degrees of spermatogenic dysfunction. Furthermore, a list of X-linked genes (KAL1, NR0B1, AR, TEX11, FMR1, PGRMC1, BMP15 and POF1 and 2 regions genes (XPNPEP2, POF1B, DACH2, CHM and DIAPH2)) were reported to have critical roles in pubertal and reproductive deficiencies in humans, affecting only men, only women or both sexes. Mutations in these genes may be transmitted to the offspring by a dominant or a recessive inheritance.

The value of urine protein kinase Y-linked gene promoter site methylation in early diagnosis of prostate cancer / 实用医学杂志

Objective To explore the clinical value of methylation at promoter sites of urine protein kinase Y-linked(PRKY)gene in the early diagnosis of prostate cancer(PCa).Methods Urine samples were collected from 50 suspected PCa patients.After extracting DNA,the methylation levels of the PRKY gene promoter sites cg05163709,cg08045599,and cg05618150 were detected using quantitative methylation-specific PCR(qMSP).Simultaneously,the patients were divided into the benign prostatic hyperplasia(BPH)group and the PCa group.The differences in clinical indicators between the two groups were analyzed,as well as the methylation status of the PRKY gene promoter sites in the urine of the two groups of patients.The receiver operating charac-teristic(ROC)curve of PRKY promoter sites methylation was established,and the area under the curve(AUC)was calculated to analyze the diagnostic value of PRKY promoter sites methylation in PCa,and to perform com-bined diagnosis with clinical indicators.Results The methylation rates of cg05163709 and cg05618150 in urine specimens of PCa patients were significantly higher than those of BPH patients.The AUC for cg05163709 methyla-tion in diagnosing PCa was 0.762,with a sensitivity of 86.70%.It showed better performance in early screening for PCa compared to total prostate specific antigen(tPSA),percentage free prostate specific antigen(f/tPSA)and prostate specific antigen density(PSAD)index.We found that the AUC for cg05618150 methylation in conjunc-tion with PSAD in diagnosing PCa was 0.787,with a sensitivity of 86.70%.The AUC of cg05163709 methylation and PSAD in the joint diagnosis of PCa was 0.855,and the specificity could reach 95.00%.Conclusion The methylation of urine PRKY gene promoter sites cg05163709 and cg05618150 shows high sensitivity and specificity in diagnosing PCa,making them promising biomarkers for early detection of PCa.

Demonstration of viability and fertility and development of a molecular tool to identify YY supermales in a fish with both genotypic and environmental sex determination.

The pejerrey possesses a genotypic sex determination system driven by the amhy gene and yet shows marked temperature-dependent sex determination. Sex-reversed XY females have been found in a naturally breeding population established in Lake Kasumigaura, Japan. These females could mate with normal XY males and generate YY "supermale" individuals that, if viable and fertile, would sire only genotypic male offspring. This study was conducted to verify the viability, gender, and fertility of YY pejerrey and to develop a molecular method for their identification. Production of YY fish was attempted by crossing a thermally sex-reversed XY female and an XY male, and rearing the progeny until sexual maturation. To identify the presumable YY individuals, we first conducted a PCR analysis using amhy-specific primers to screen only amhy-positive (XY and YY) fish. This screening showed that 60.6% of the progeny was amhy-positive, which suggested the presence of YY fish. We then conducted a second screening by qPCR in order to identify the individuals with two amhy copies in their genome. This screening revealed 13 individuals, all males, with values twice higher than the other 30 amhy-positive fishes, suggesting they have a YY complement. This assumption as well as the viability, fertility, and "supermale" nature of these individuals was confirmed in progeny tests with XX females that yielded 100% amhy-positive offspring. These results demonstrate that qPCR can obviate progeny test as a means to identify the genotypic sex and therefore may be useful for the survey of all three possible genotypes in wild populations.