P–020 AZFc partial microdeletions of the Y chromosome is associated with severe oligozoospermia among Iranian men

Study question Are AZFc partial deletions correlated with severe oligozoospermia in Iranian men? Can we consider them as risk factors for infertility? Summary answer The frequency of total partial AZFc microdeletions was significantly higher in the oligozoospermia group compared to control group (8% vs. 3%, P = 0.028). What is known already Among many factors affecting male infertility, the second most common genetic factor is Y chromosome microdeletion. Some studies on partial AZFc microdeletions (especially on three major types; gr/gr, b1/b3 and b2/b3) have associated them with impaired spermatogenesis (azoospermia and oligozoospermia) in infertile men from different ethnicities. This finding is attributed to differences in alterations in pattern of DAZ/CDY1 copy numbers as spermatogenesis related genes. Study design, size, duration 200 oligozoospermic (sperm count <5 mil./mL) and 200 fertile men were included as case and control groups, respectively. Individuals with karyotype abnormalities, complete microdeletions in AZF regions, infections, hypogonadism, history of chemotherapy and radiation, cryptorchidism or history of orchiopexy were not included. The study was approved by the Royan Institute Ethics Committee. Written informed consents were obtained from each participant. Participants/materials, setting, methods Total DNA from peripheral blood was used to amplify six sequence-tagged sites (STS) markers through multiplex PCR to detect AZFc partial deletions according to previous studies. Patterns of deletion in DAZ and CDY1 copies were determined through PCR- RFLP. Main results and the role of chance The frequency of AZFc partial microdeletions was 8% in oligozoospermic men (16/200) which was significantly higher compared to 3% in control group (6/200) (P = 0.028). Hence, partial deletions may be considered as a risk factor for the male infertility in Iranian population. Also, gr/gr showed a higher frequency in oligozoospermic group (4%) compared to controls (1.5%) (P = 0.126). The combination of DAZ1/2+CDY1b was the most observed deletion pattern in 8 oligozoospermic men with gr/gr deletion (75%), while among 3 controls with gr/gr, DAZ3/4+CDY1a (2 out of 3) and DAZ3/4+CDY1b (1 out of 3) were detected. Therefore, DAZ1/2+CDY1b can be correlated to oligozoospermia. Limitations, reasons for caution In order to achieve stronger statistical results, a larger sample size is of more help. Wider implications of the findings: Risk of vertical transmission to male offspring and expansion in the size of deletions should be considered when providing ART services to infertile men. Genetic counseling is suggested in oligozoospermic men. Trial registration number -

Molecular characterization of the Yp11.2 region deletion in the Chinese Han population

The Y chromosome is male-specific and is important for spermatogenesis and male fertility. However, the Y chromosome is poorly characterized due to massive palindromes and inverted repeats, which increase the likelihood of genomic rearrangements, resulting in short tandem repeats on the Y chromosome or long fragment deletions. The present study reports a large-scale (2.573~2.648 Mb) deletion in the Yp11.2 region in a Chinese population based on the analysis of 34 selected Y-specific sequence-tagged sites and subsequent sequencing of the breakpoint junctions on the Y chromosome from 5,068,482–5,142,391 bp to 7,715,462–7,716,695 bp. The results of sequence analysis indicated that the deleted region included part or all of the following five genes: PCDH11Y, TSPY, AMELY, TBL1Y, and RKY. These genes are associated with spermatogenesis or amelogenesis and various other processes; however, specific physiological functions and molecular mechanisms of these genes remain unclear. Notably, individuals with this deletion pattern did not have an obvious pathological phenotype but manifested some degree of amelogenesis imperfecta.

Evaluation of Y chromosome microdeletions and chromosomal anomalies in infertile men

Objectives Chromosome anomalies and Y chromosome microdeletions are one of the reasons that can be seen in infertile patients and affect fertility. In this study, it was aimed to determine the frequencies of chromosomal anomalies and Y chromosome microdeletions in primary infertile male patients. Methods We included 374 patients with primary infertility in this study. Cytogenetic analysis was performed with the GTG banding technique by using trypsin and Giemsa stain. Y microdeletion analysis was studied by multiplex polymerase chain reaction using 28 Y chromosome-specific sequence-tagged sites. Results Chromosomal irregularities were detected in 27 (7.22%) of infertile cases. It was observed that 7 (25.92%) of chromosomal irregularities detected in cases were in autosomal and 20 (%74.08) were in gonosomal chromosomes. The incidence of Y chromosome microdeletion was 1.07% (4/374) and the microdeletions were observed in AZFb, AZFc and AZFd regions. AZFc + AZFd deletion was detected in three patients (0.81%) and AZFb + AZFc + AZFd deletion in one patient (0.26%). Conclusions In conclusion, gonosomal chromosome irregularity was higher than autosomal chromosome irregularity in infertile men. The frequency of Y microdeletion has different rates according to some factors such as ethnic differences of patients, patient selection criteria, differences in the number of cases, and methodological aspects.

Y chromosome microdeletion and cytogenetic findings in male infertility: A cross-sectional descriptive study

Background: Infertility affects about 15% of couples worldwide, and the male factor alone is responsible for approximately 50% of the cases. Genetic factors have been found to play important roles in the etiology of azoospermia and severe oligospermia conditions that affect 30% of individuals seeking treatment at infertility clinics. Objective: To determine the frequency of chromosomal abnormalities and Y chromosome microdeletion in infertile men. Materials and Methods: A total of 100 infertile men with abnormal semen parameters were included in this study from 2014 to 2018. Chromosomal analysis was carried out using standard G-banding using Trypsin Giemsa protocol. Multiplex polymerase chain reaction was used to determine the Y microdeletion frequency. Results: All participants were aged between 22 and 48 yr with a mean and standard deviation of 35.5 ± 5.1. Of the 100 subjects included in the study, three had Klinefelter syndrome-47,XXY, one had balanced carrier translocation- 46,XY,t(2;7)(q21;p12), one with the balanced carrier translocation with inversion of Y chromosome 45,XY,der(13;14)(q10;q10),inv(Y), one had polymorphic variant of chromosome 15, one had Yqh-, and another had an inversion of chromosome 9. Y chromosome microdeletion of Azoospermia factor c region was observed in 2% of the cases. To the best of our knowledge, the current study is the first reported case with unique, balanced carrier translocation of chromosome 2q21 and 7p21. Conclusion: The present study emphasizes the importance of routine cytogenetic screening and Y microdeletion assessment for infertile men, which can provide specific and better treatment options before undergoing assisted reproductive technology during genetic counseling. Key words: Chromosome aberrations, Infertility, Chromosome deletion, Polymerase chain reaction, Sequence tagged sites.

Development of RNA-seq-based molecular markers for characterizing Thinopyrum bessarabicum and Secale introgressions in wheat

Sequence-based markers have added a new dimension in the efficiency of identifying alien introgressions in wheat. Expressed sequence tag-sequence tagged sites (EST-STS) markers have proved useful in tracing alien chromatin. In this study, we report the development of Thinopyrum bessarabicum- and Secale anatolicum-specific EST-STS markers and their application in tracing respective alien chromatin introgressions in wheat. The parental lines, Chinese Spring (CS), ISR991.1 (CS/Th. bessarabicum amphidiploid), and ISR1049.2 (CS/Secale anatolicum amphidiploid), were used as core experimental materials. Using comparative analysis of RNA-Seq data, 10 903 and 10 660 candidate sequences specific to Th. bessarabicum and S. anatolicum, respectively, were assembled and identified. To validate the genome specificity of these candidate sequences, 68 and 64 EST-STS markers were developed from randomly selected candidate sequences of Th. bessarabicum and S. anatolicum, respectively, and tested on sets of alien addition lines. Fifty-five and 53 markers for Th. bessarabicum and S. anatolicum chromatin, respectively, were assigned to chromosomal location(s), covering all seven chromosomes. Approximately 83% of S. anatolicum-specific markers were transferable to S. cereale. The genome-specific candidate sequences identified and the EST-STS markers developed will be valuable resources for exploitation of Th. bessarabicum and Secale species diversity in wheat and triticale breeding.

Mosaic Ring-like Small Supernumerary Marker Chromosome and Gene Mutation in a Male With Intermittent Azoospermia: A Rare Case Report

This study aimed to report a rare case of intermittent azoospermia and ring-like small supernumerary marker chromosomes (sSMCs). An infertile man was diagnosed with azoospermia presenting a normal male phenotype with complete masculinization. Karyotyping and polymerase chain reaction (PCR) were used to detect 16 sequence-tagged sites on the AZF subregions of the Y chromosome, and 115 candidate genes were screened for mutations. Mutations included single nucleotide variations, insertions, and deletions. Metaphase chromosomes were studied by standard trypsin-Giemsa banding; fluorescent in situ hybridization and PCR were performed to analyze specific Y chromosome regions; gene mutations were detected. Chromosomal analysis detected 117 metaphase cells; a mosaicism with marker 1 and marker 2 sSMCs in 2 metaphase cells (47, X, +mar1x2 karyotype), a mosaicism with marker 2 sSMCs in 14 metaphase cells (46, X, +mar2 karyotype), and a mosaicism with marker 1 sSMCs in 76 metaphase cells (46, X, +mar1 karyotype), coexisting with a 45,X cell line in the remaining 25 metaphase cells. PCR analysis showed the sY160 heterochromosome on the AZFc subregion was absent. Next-generation sequencing identified an asthenozoospermia-specific mutation in GAPDHS (rs2293681), and Sanger sequencing verified this mutation. This gene encodes a protein belonging to the glyceraldehyde-3-phosphate dehydrogenase family of enzymes that play an important role in carbohydrate metabolism. Like its somatic cell counterpart, this sperm-specific enzyme functions in a nicotinamide adenine dinucleotide-dependent manner to remove hydrogen and add phosphate to glyceraldehyde 3-phosphate to form 1,3-diphosphoglycerate. During spermiogenesis, this enzyme may play an important role in regulating the switch between different energy-producing pathways, and it is required for sperm motility and male fertility. A mosaic 46, X, +mar1[76]/45, X[25]/46, X, +mar2[14]/47, X, +mar1x2[2] karyotype could be the main explanation for the azoospermia/severe oligospermia, while the likely pathogenic GAPDHS intron mutation may contribute to the symptom of immotile sperms detected in the semen analysis.

Chromosomal abnormalities and Y chromosome microdeletions in infertile men with azoospermia and oligozoospermia in Eastern China

Objective The objective was to investigate the frequency and type of chromosomal abnormalities and Y chromosome microdeletions in infertile men with azoospermia and oligozoospermia to ensure appropriate genetic counseling before assisted reproduction in Eastern China. Methods A total of 201 infertile men (148 with azoospermia and 53 with oligozoospermia) were enrolled. Real-time PCR using six Y-specific sequence-tagged sites of the azoospermia factor (AZF) region was performed to screen for microdeletions. Karyotype analyses were performed on peripheral blood lymphocytes with standard G-banding. Results Out of 201 infertile patients, 22 (10.95%) had Y microdeletions [17/148 (11.49%) men with azoospermia and 5/53 (9.43%) men with oligozoospermia]. The most frequent microdeletions were in the AZFc region, followed by the AZFa+b + c, AZFb+c, AZFa, and AZFb regions. Chromosomal abnormalities were detected in 18.91% (38/201) of patients, 34 of which were sex chromosome abnormalities (16.92%) and 4 of which were autosomal abnormalities (1.99%). Chromosomal abnormalities were more prevalent in men with azoospermia (22.97%) than in those with oligozoospermia (7.55%). Conclusions We detected a high incidence of chromosomal abnormalities and Y chromosomal microdeletions in infertile Chinese men with azoospermia and oligozoospermia. These findings suggest the need for genetic testing before the use of assisted reproduction techniques.

Molecular microdeletion analysis of infertile men with karyotypic Y chromosome abnormalities

Objectives To investigate azoospermic factor (AZF) microdeletions in infertile men from northeastern China with karyotypic Y chromosome abnormalities. Methods G-banding of metaphase chromosomes and karyotype analysis were performed in all infertile male patients. Genomic DNA was isolated and used to analyze classical AZF microdeletions by PCR. The regions and sequence-tagged sites of AZFa (SY86, SY84), AZFb (SY127, SY134, SY143), and AZFc (SY152, SY254, SY255, SY157) were sequenced by multiplex PCR. Results A total of 190 Y chromosome abnormality carriers were found, of whom 35 had AZF microdeletions. These were most common in 46,X,Yqh− patients, followed by 45,X/46,XY patients. Most microdeletions were detected in the AZFb + c region, including 48.57% of all AZF microdeletion cases. AZF partial deletions were also seen in these patients. Overall, AZF microdeletions were detected in 38.5% Y chromosome abnormality carriers, and most were observed in 46,X,Yqh− individuals. Loss of SY152 was seen in all 35 patients, with SY254/SY255 detected in 34 of 35 patients. Conclusions AZF microdeletions were detected in 38.5% of Y chromosome abnormality carriers. This indicates that AZF microdeletion screening is advisable for individuals with karyotypic Y chromosome abnormalities.

Clinical, Hormonal, and Genetic Evaluation of Idiopathic Nonobstructive Azoospermia and Klinefelter Syndrome Patients

To investigate the clinical, hormonal, and genetic factors in infertile men with idiopathic nonobstructive azoospermia (NOA) or azoospermic Klinefelter syndrome (KFS), a total of 556 and 96 patients, respectively, were included in this study. All patient samples were analyzed cytogenetically. Serum reproductive hormone levels were measured. Microdeletions in the azoospermia factor (AZF) region of the Y chromosome were detected by multiplex PCR using 16 specific sequence-tagged sites. FSH and LH levels in both NOA and KFS patients were significantly higher than the normal range, and the testosterone level in KFS patients was significantly lower. Ninety-two (95.8%) of the KFS patients showed non-mosaic 47,XXY karyotypes and 47,XXY,inv(9)(p11.1q13); the other KFS patients had mosaic karyotypes of 47,XXY/46,XY, 47,XXY/46,XX, and 47,XXY/48,XXXY/46,XX. Among the 556 idiopathic NOA patients with normal karyotypes, 67 (12.05%) had microdeletions in the AZF region of the Y chromosome. Microdeletions were most frequently detected in the AZFc region, followed by AZFa, AZFb, AZFbc, and partial AZFc deletions. However, Y chromosome microdeletions were not found in any of the azoospermic KFS patients. In view of the hormonal and genetic abnormalities in infertile men with idiopathic NOA and with azoospermic KFS, genetic testing for karyotype, Y chromosome microdeletions, and hormonal parameters is advocated.