Chromosomal Abnormalities and Y Chromosome Microdeletions in Infertile Men With Varicocele and Idiopathic Infertility of South Indian Origin

The Evolving Landscape of Male Varicocele Pathophysiology in the Era of Multi-Omics: A Narrative Review of the Current Literature

Male-factor infertility is implicated in over half of the millions of cases of infertility worldwide, and varicoceles are the most common correctable cause of male-factor infertility. The pathophysiologic mechanism for varicoceles is complex and next-generation technologies offer promising insights into the molecular underpinnings of this condition. In this narrative review, we highlight historical and contemporary paradigms associated with varicoceles, with an emphasis on the biological underpinnings of this disease. Specifically, we review the literature describing the underlying causes of varicoceles, discuss the molecular and cellular mechanisms causing pathological changes in some (but not all) men, and highlight key articles regarding the next-generation analyses (e.g., transcriptome, epigenome, proteome, and microbiome) being applied to better understand the condition and its treatment. These data demonstrate an ongoing evolution of the knowledge of varicoceles and the potential for improved personalized care in the future for men with this condition.

Role of Oxidative Stress in Varicocele

According to the official statistics of the World Health Organization, at least 48 million couples and 186 million people suffer from infertility. Varicocele has been recognized as the leading cause of male infertility and can affect spermatogenesis and cause testicular and epididymal disorders through multiple diverse pathophysiological processes. Reactive oxygen species (ROS) produced by oxidative stress have been reconciled as an important pathogenic factor throughout the course of varicocele. Testis respond to heat stress, hypoxia, and inflammation at the cost of producing excessive ROS. High levels of ROS can lead to infertility not only through lipid peroxidation or DNA damage, but also by inactivating enzymes and proteins in spermatogenesis. This review studies the oxidative stress and its role in the pathophysiology and molecular biology of varicocele in the context of a decline in fertility.

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.

Clinical presentations and semen characteristics of men attending the secondary referral infertility clinic at Mumbai, India

Background:

Limited information is available on the aetiology and semen profiles of male infertility in Indian population.

Aim:

The aim of this study is to study the clinical and semen characteristics of men attending the infertility clinic and also to understand the impact of World Health Organization (WHO) 2010 reference values on the diagnosis of male infertility.

Setting and Design:

A retrospective study evaluating the medical case records (January 2005 to December 2015, [n = 1906]) of men attending infertility clinic in Mumbai, India.

Materials and Methods:

The aetiology was classified based on the andrology evaluation and other investigations. Semen profiles were compared during the years 2005–2010 and 2011–2015 using WHO 1999 and WHO 2010 criteria, respectively.

Statistical Analysis:

The Chi-square and Mann–Whitney U tests were performed using Open Source Epidemiological software and Social science calculators.

Results:

The aetiology of male infertility was determined in 62% of the men; while the cause remained undetermined in 38%. Varicocele (25%), urogenital infections (10%), sexual dysfunctions (8%) and vas aplasia (8%) were identified as major aetiologies in our cohort. Men with sexual dysfunctions and vas aplasia were significantly higher during the years 2011–2015 as compared to 2005–2010. Men having normozoospermia (10%) and azoospermia (3%) were increased, whereas those having oligoasthenozoospermia (17%) were reduced in 2011–2015 as compared to 2005–2010. According to WHO 1999 criteria , 12-15% of men showed abnormal semen profiles. The semen parameters of these men became normal on using WHO 2010 reference values.

Conclusions:

Varicocele is the most common aetiology in infertile men. Idiopathic infertility was seen in a higher proportion among the infertile men.

A familial analysis of two brothers with azoospermia caused by maternal 46,Y, t(X; 1) (q28; q21) chromosomal abnormality

Chromosomal abnormality is a primary genetic factor that lead to azoospermia and male infertility. Here, we report the cases of two brothers with primary infertility, whose chromosomes displayed a balanced translocation, and their karyotypes were 46,Y, t(X; 1) (q28; q21). Both presented an azoospermia phenotype without abnormal clinical symptoms. Their mother's karyotype was 46,X, t(X; 1) (q28; q21), and their father's chromosome karyotype was 46,XY. No abnormal changes were noted in the copy number of chromosome fragments in the whole genome. This study is the first to report showing that 46,Y, t(X; 1) (q28; q21) chromosomal abnormalities are associated with azoospermia.

Clinical aspects of 49 infertile males with 45,X/46,XY mosaicism karyotype: A case series

Disorders of sex development (DSD) are congenital abnormalities as an atypical development process in either gonadal or chromosomal structure. It is the cause of the abnormality in phenotype and characteristics. Chromosomal analysis plays an important role in the DSD determination. 45,X/46,XY mosaicism is a rare karyotype, and its prevalence is about 1.5 in 10,000 newborns. It affects the growth, hormonal balance, gonad development and histology. All data such as height, male general appearance, testis size and volume, external genitalia, spermogram and hormonal levels, testis pathology, Y chromosome microdeletion and karyotype, and assisted reproductive technology (ART) outcome were recorded based on patients profile and history. We investigated 64 infertile males with 45,X/46,XY mosaicism. Fifteen cases who had structural abnormalities in Y chromosome were excluded. From 49 available spermogram, 21 cases reported as azoospermic men, while 28 of them classified as nonazoospermic patients in which four of them displayed normal spermogram. According to hormonal evaluation, there were no significant differences between azoospermic and nonazoospermic groups. In azoospermia, only three couples underwent an ART cycle in which all of them failed. From 14 nonazoospermic cases who entered into the ART cycle, three cases experienced a successful pregnancy that one of the prosperous outcomes was twins. In 45,X/46,XY cases, both 45,X and 46,XY cell lines are seen. Various distributions of both cell lines can reflect a wide range of phenotypes that may be the most comprehensive evaluation in infertile males with 45,X/46,XY karyotype. It assumes that karyotyping as a main diagnostic test can enable us to find these rare cases.

Y chromosome microdeletions and varicocele as aetiological factors of male infertility: A cross-sectional study

The pathogenic mechanisms by which varicocele disrupt spermatogenesis are not clearly understood. Over 30% of male infertility cases resulting from spermatogenic problems are associated with genetic abnormalities, and Y chromosome microdeletions are the second most frequent genetic cause. Here, we aimed to evaluate the frequency of Y chromosome microdeletion in infertile men with varicocele. A cross-sectional study comprising 51 infertile men with varicocele presenting spermatogenesis failures was performed. Y chromosome microdeletion research was made using polymerase chain reaction. Of the 51 men with infertility and varicocele, 35.3% (18/51) had nonobstructive azoospermia and 64.7% had severe oligozoospermia. Y chromosome microdeletion was found in two cases (3.9%): one patient had nonobstructive azoospermia and complete microdeletion of the AZFb and AZFc regions, and another patient had severe oligozoospermia and complete microdeletion of the AZFc region. Although in recent years, a genetic aetiology related to Y chromosome microdeletions has become a major cause of infertility in males with spermatogenesis failures, in this study, the varicocele was the clinical cause of seminal abnormalities that could lead to infertility, suggesting that both varicocele and Y chromosome microdeletion aetiologies can present, alone or combined, as factors of male infertility.

Clinical and Para Clinical Information Needs of Infertility Electronic Health Records in Iran: A Delphi Study

Background:

infertility is referred to the person’s inability to conceive pregnancy after one year of intercourse without using protection. This study paves the ground for creating a complete, united, and coherent source of patients’ medical information.

Materials and Methods:

this is an applied research of descriptive-cross sectional type which has been carried out through qualitative – quantitative methods. The sample of the present study was 50 specialists in the field of infertility which has been chosen based on purposive sampling method. Designing the questionnaire was done based on library studies and Gathering experts’ views was done based on Delphi technique.

Results:

261 items from clinical and Para clinical information of infertile patients’ electronic health records were subjected to an opinion poll by experts. During this process 223 items were accepted and 38 items have been rejected after two sessions of surveys by infertility experts. Para clinical information section consisted of 57 items that all of them have been accepted by the experts. Also, clinical information section consisted of 242 items from which 204 items were accepted and 38 items were rejected by the experts.

Conclusion:

existence of a structured electronic record system of infertile patients’ information leads to the integration of patients’ information, improvement of health care services and a decrease in treatment costs: all working to increase information safety. Furthermore, only essential and relevant information would be provided for the specialists and it will facilitate and direct the future infertility related studies due to the coherence, unity and relevance of the information.

Genetics and epigenetics of varicocele pathophysiology: an overview

Varicocele is found in approximately 20% of adults and adolescents and in 19-41% of men seeking treatment for infertility. It is associated with a decrease in sperm count as well as sperm motility and morphology. The currently accepted description of the pathophysiology of varicocele does not explain all its clinical manifestations; therefore, other factors such as genetic and epigenetic changes, associated with the environment, might be involved in causing infertility and decrease in sperm quality. It has been reported that the varicocele-induced deterioration of testicular function is progressive and interferes with fertility; hence, early and efficient assessment of the genetic manifestations in patients would be important for developing future medical interventions. Chromosomal disorders, mutations, polymorphisms, changes in gene expression, and epigenetic changes have all been reported to be associated with varicocele. Several studies are underway to unravel the genetic basis of this disease, as it is important to understand the origin and the aggravating factors to ensure appropriate guidance and intervention. Here, we review the available literature regarding the genetic and epigenetic changes associated with varicocele, and how these alterations are related to the different clinical manifestations of the disease.

Correlation of genetic results with testicular histology, hormones and sperm retrieval in nonobstructive azoospermia patients with testis biopsy

To investigate the frequency and types of genetic results in different testicular histology of patients with nonobstructive azoospermia (NOA), and correlated with hormones and sperm retrieval (SR), a retrospective study was conducted in 286 Chinese NOA patients who underwent testis biopsy and 100 age-matched fertile men as the control group. Chromosome karyotype analyses were performed by the peripheral blood chromosome G-band detection method. Screening of Y chromosome microdeletions of azoospermia factor (AZF) region was performed by polymerase chain reaction (PCR) amplification of 11 sequence-tagged sites (STS). The serum levels of follicle-stimulating hormone, luteinising hormone and testosterone (T) and the appearance of scrotal ultrasound were also obtained. In 286 cases of NOA, 14.3% were found to have chromosomal alterations. The incidence of chromosomal abnormality was 2.8%. Sex chromosomal abnormalities were seen in six cases (four cases of Klinefelter's syndrome (47, XXY) and two cases of mosaics). The incidence of polymorphic chromosomal variants was 3% in the normal group and 11.5% in the NOA group. In total, 15.7% of NOA patients were found to have AZF microdeletions and AZF (c + d) was the most frequent one. The results of hormone and SR were found to be significantly different among all testicular histological types, whereas no significant differences were found when it comes to genetic alterations. It is concluded that the rate of cytogenetic alterations was high in NOA patients. So screening for chromosomal alterations and AZF microdeletions would add useful information for genetic counselling in NOA patients with testis biopsy and avoid vertical transmission of genetic defects by assisted reproductive technology.

Prevalence of Y Chromosome Microdeletions in Idiopathic Azoospermia Cases in Central Indian Men

BACKGROUND

Genetic factor is important determinant of human male fertility, it is involved in 10-15% infertile males. Chromosome abnormalities and Y chromosome microdeletions are the main genetic causative factors for infertility. The frequency of male infertility & microdeletions in Y chromosome are also related to ethnic, geographical variations. In this study, we evaluated the prevalence of chromosomal abnormalities and microdeletions of Y chromosome in infertile azoospermia cases in central India to assess the geographical or population based variations.

MATERIALS AND METHODS

We have studied 160 non-obstructive azoospermia cases to find out frequency of chromosomal abnormalities and Y chromosome microdeletions of AZF locus. G-banding method was used for exclusion of chromosomal abnormalities. One hundred and forty eight azoospermic infertile men were screened using 12 sequence-tagged-sites (STS) primers of AZFa, AZFb, AZFc region and SRY gene (Yp) region by polymerase chain reactions.

RESULTS

Out of 160 azoospermic infertile males, 12 (7.5%) confirmed chromosomal abnormalities and Klinefelter's syndrome was predominantly cause of azoospermia. Of the 148 infertile males, 19 (12.8%) were shown microdeletions in different AZF regions. Deletions in AZFa region were 2.02% and 3.37% was in AZFb whereas high frequencies of deletions (6.08%) in AZFc were recorded in azoospermic males. In two azoospermic males were shown microdeletions in AZFb+c loci.

CONCLUSION

The prevalence of Y chromosome microdeletions in azoospermic men was 12.8% in this geographical region. Klinefelter's syndrome is important cause in male infertility. So, the screening of Y microdeletions is essential.

Chromosomal aberrations and polymorphic evaluation in males with primary infertility from Indian population

BACKGROUND AND OBJECTIVES

The chromosomal abnormalities are one of the important causes of male infertility. In view of the genetic risks for the next generation, the importance of careful evaluation of karyotype is essential. The objective of this study was to determine the frequency of chromosomal abnormalities in infertile men with primary infertility from Indian population.

MATERIALS AND METHODS

The 78 infertile men with primary infertility, out of which 26 men were azoospermic, 19 men were oligospermic, 4 men were asthenospermic and 29 men were oligoasthenospermic were studied. Karyoptying was performed on peripheral blood lymphocytes by using the Giemsa trypsin banding (GTG) banding technique. Additional data was collected from published studies in Indian population leading to a total of 1814 cases.

RESULTS

Chromosome analysis of 78 infertile males showed major chromosome abnormalities in 10.2%, with 6.4% in autosomal chromosome abnormalities and 3.8% in sex chromosome abnormalities. The incidence of major chromosome abnormalities in oligospermic males were 21% and azoospermic males were 15.4 %. Chromosomal polymorphic variants were identified to be 16.7%. Combining the data from other published studies identified 153/ 1814 (8.4%) infertile men of chromosomal abnormalities; with 10.8% in azoospermia, 7.3% in oligospermia and 7.3% in oligoasthenoteratospermic from India.

INTERPRETATION AND CONCLUSION

The overall high prevalence of chromosomal abnormalities in infertile males suggests that the conventional chromosomal analysis is an important investigative tool for male infertility, especially prior to use of any assisted reproductive techniques.

High prevalence of genetic abnormalities in Middle Eastern patients with idiopathic non-obstructive azoospermia

INTRODUCTION

Our objective is to detect the frequency and types of major genetic abnormalities of idiopathic non-obstructive azoospermia (NOA) to give appropriate genetic counseling before assisted reproductive techniques (ART) in Middle East and to compare the frequencies with other regions of the world.

MATERIAL AND METHODS

A total of 880 Middle Eastern patients with NOA were recruited in this multicenter study for genetic evaluation prior to use of ART. Karyotyping was performed on peripheral blood lymphocytes according to standard G-banding methods, polymerase chain reaction (PCR) was performed to screen the microdeletions in the AZF region of the Y chromosome.

RESULTS

The present study shows that the total prevalence of genetic abnormalities is 28.41 %, including 184 patients (20.91 %) with chromosome disorder and 66 patients (7.5 %) with Y chromosome microdeletions. The most prevalent chromosome abnormality is Klinefelter's syndrome, which includes 161 patients (18.3 %), 7 patients had XX reversal male sex (0.8 %), 2 patients had 47XYY (0.23 %) and 2 patients had 45XO/46XY (0.23 %). Structural abnormalities occurred in 12 patients (1.36 %).

CONCLUSIONS

The high prevalence of genetic abnormalities (28.41 %) in our study strongly suggests the need for routine genetic testing and counseling prior to assisted reproduction in such population with idiopathic infertility, as a result may help determine the prognosis, as well as the choice of ART. Moreover it allows specific pre-implantation genetic testing to minimize the risk of transmitting genetic defects to offspring.

Y chromosome microdeletions in infertile men: prevalence, phenotypes and screening markers for the Indian population

PURPOSE

Yq microdeletions are the leading genetic cause of male infertility and its detection is clinically relevant for appropriate genetic counseling. We aimed to determine the prevalence and type of Yq microdeletions, the associated seminal phenotypes and the STS markers that are relevant for its testing in Indian population.

METHODS

Yq microdeletion analysis was carried out in 1,636 infertile cases in our centers. Additional data was collected from published studies in Indian population leading to a total of 3,647 cases.

RESULTS

In our cohort, 3.4 % (56/1,636) of infertile men had Yq microdeletions. Combining the data from other published studies identified 215/3,647 (5.8 %) infertile individuals to harbor Yq microdeletions; with 6.4 % in azoopsermia, 5.8 % in oligozoospermia and 3.2 % in oligoasthenozoospermia and teratozoospermia cases. No significant differences in the deletion frequencies were observed between idiopathic vs non idiopathic cases (5.8 vs 8.6 % respectively). Deletions of AZFc were at highest frequency (46.6 %) with double deletions most commonly observed in azoospermic subjects. With respect to the STS markers, screening with the six European Academy of Andrology (EAA) markers would miss 3.1 % of cases; additional non EAA markers that would contribute significantly to screening are sY746, sY82, sY121, sY128, sY130, sY143, sY145 & sY160.

INTERPRETATIONS AND CONCLUSIONS

The frequency of Yq microdeletions is lower in Indian population as compared to Western counterparts. There is no major association of Yq microdeletions with seminal parameters or cause of infertility. Clinically it will be necessary to offer Yq microdeletion testing to all the classes of infertile men. The EAA markers may not be adequate to detect microdeletions in Indian infertile men.

The role of varicocele treatment in the management of non-obstructive azoospermia

The literature on male reproductive medicine is continually expanding, especially regarding the diagnosis and treatment of infertility due to non-obstructive azoospermia. The advent of in vitro fertilization with intracytoplasmic sperm injection has dramatically improved the treatment of male infertility due to nonobstructive azoospermia. Assisted reproduction using testicular spermatozoa has become a treatment of hope for men previously thought to be incapable of fathering a child due to testicular failure. In addition, numerous studies on non-obstructive azoospermia have reported that varicocelectomy not only can induce spermatogenesis but can also increase the sperm retrieval rate; however, the value of varicocelectomy in patients with non-obstructive azoospermia still remains controversial. The purpose of this review is to present an overview of the current status of varicocele repair in men with non-obstructive azoospermia.

Cytogenetic abnormalities in 222 infertile men with azoospermia and oligospermia in Iran: Report and review

BACKGROUND:

Infertility affects approximately 10%-15% of couples in reproductive age. In half of the couples, causes are male-related, associated with impaired spermatogenesis. There is a complex correlation between genetics and infertility. Several factors affect on gametogenesis, from which factors that lead to chromosomal abnormalities are one of the best known. The aim of this study was to determine type and rate of chromosomal abnormalities in infertile azoospermic and oligospermic males in Iranian population.

MATERIALS AND METHODS:

The records of a total of 222 participants were evaluated retrospectively.

RESULTS:

As a whole we observed 13.96% chromosomal abnormality, from which 12.15% showed numerical and 1.8% showed structural abnormalities.

CONCLUSION:

Comparison of our results with the review of the literature shows a higher incidence (4- fold) of gonosomal, in particular, numerical gonosomal, chromosomal anomalies. Cytogenetic analysis is strongly suggested for infertile men, particularly in those who suffer from azoospermia.

Genetic evaluation of severe male factor infertility in Turkey: a cross-sectional study

OBJECTIVE

To determine the frequency, types of chromosomal abnormalities and Y chromosome microdeletions in patients with severe male factor infertility, and the association between clinical background and genetic abnormality.

STUDY DESIGN

A total of 322 infertile men; 136 men with severe oligozoospermia (sperm count <5 million/ml) and 196 with nonobstructive azoospermia were studied between April 2004 and November 2006 at the Dr. Zekai Tahir Burak Women's Health Education and Research Hospital, Ankara, Turkey. Blood, semen samples, and testicular biopsies of patients were obtained. Hormonal analysis (follicle-stimulating hormone (FSH), luteinizing hormone (LH), and testosterone levels), semen analysis, karyotype analysis, and PCR screening for Y chromosome microdeletions were performed.

RESULT(S)

Forty-eight out of 332 (14%) infertile men had a genetic abnormality. Twenty-four (7.2%) cases with karyotype abnormality were detected. The frequencies of karyotype abnormalities were Klinefelter's syndrome 17/24 (71%), translocation 3/24 (12%), mix gonadal dysgenesis 2/24 (8%), XX male 1/24 (4%), and 46XYY 1/24 (4%). Twenty cases (6%) infertile men had only Y chromosome microdeletions. The frequencies of the deleted areas were azoospermia factor (AZF)c 42%, AZFb 25%, AZFa 21%, AZFb, c 8%, and AZFa, c 4%. Four of the cases with Y chromosome microdeletions also had a concurrent karyotype abnormality.

CONCLUSION(S)

All patients with nonobstructive azoospermia and severe oligozoospermia (sperm count <5 million/ml) should undergo genetic screening.

Use of ethnicity-specific sequence tag site markers for Y chromosome microdeletion studies

INTRODUCTION

Microdeletions in the azoospermia factor region on the long arm of Y chromosome are associated with spermatogenic failure. There are many markers for the diagnosis of Y chromosome microdeletion analysis, but in routine practice only a limited set of markers can be tested.

OBJECTIVE

The objectives of this study were to determine the frequency of Y chromosome microdeletion in idiopathic cases of male infertility in India, to attempt genotype-phenotype correlation, and to evaluate whether markers to be tested for diagnosis of Y chromosome microdeletion should be ethnicity specific.

METHODS

Microdeletions in the Y chromosome were analyzed in 200 infertile males. The six sequence tag site (STS) markers prescribed by the European Academy of Andrology (EAA) were used initially. Patients in whom no deletions were detected by use of these markers were tested by markers selected from other studies from India.

RESULTS

The STS markers prescribed by EAA detected deletions in only 6 (3%) of 200 infertile males. However, markers selected from previous Indian studies showed deletions in an additional 15 (7.5%) of infertile males. Overall, Y chromosome microdeletions were observed in 21 (10.5%) of 200 patients. Of these, 13 were cases of azoospermia and 8 were cases of severe oligospermia.

CONCLUSION

The markers prescribed by EAA alone are not suitable for the diagnosis of Y chromosome microdeletions in infertile males. The protocol for identification of Y chromosome microdeletions in cases of nonobstructive azoospermia/severe oligospermia would have to include a different set of STS markers.

Analysis of azoospermia factor loci polymorphisms among Tunisian infertile men with varicocele

AIMS

The preponderance of experimental data from clinical and animal models demonstrates an adverse effect of varicocele on spermatogenesis. The review of the literature shows that there may be an underlying genetic etiology in varicocele. Here, we explore the Yq microdeletions among infertile men to evaluate their involvement in varicocele development and sperm production defect.

RESULTS

Microdeletions of 14 sequence-tagged-sites in the Yq11 region were screened in 210 infertile men using polymerase chain reaction techniques. Out of 210 infertile men, 69 (33%) men were with varicocele. Our results showed that the risk to develop varicocele is increased among infertile men with spermatogenesis (oligo-normospermia) (odds ratio = 3.57, confidence interval 95%: 1.49-8.84). However, we did not find any relationship between Y chromosome microdeletions and varicocele appearance (p = 0.73). In addition, a significant association was found between Y microdeletions and oligospermia (p < 10(-8)) or azoospermia (p < 10(-8)) using patients with normospermic characteristics as a control.

CONCLUSION

Our work showed the absence of relationship between Y chromosome microdeletions and varicocele development and the association of the two factors, independently, with sperm production defect.

[Evaluation of a multiplex PCR kit used for detecting Y chromosome microdeletions]

BACKGROUND

In addition to Klinefelter's syndrome, microdeletion of Yq is the most common genetic cause of male infertility; 15% of azoospermic or 5-10% of oligozoospermic males have Yq deletions. We evaluated a Yq microdeletion kit (LG Life Sciences, Korea) for identifying microdeletions in the azoospermic factor (AZF) regions of the Yq.

METHODS

The kit was designed to amplify 3 regions of the AZF gene (AZFa, AZFb, and AZFc) using 15 sequence-tagged sites. We evaluated the preclinical performance of the kit. For clinical validation, 58 patients including 25 idiopathic azoospermic or oligozoospermic patients were examined.

RESULTS

We observed clear bands on electrophoresis of DNA, up to a DNA concentration of 3.12 ng/microL; the known microdeletion regions of all 6 reference cell-lines (Coriell, USA) were accurately detected and no false positive/negative results showed with normal female (n=11) and fertile male (n=15) specimens. This kit could identify the same microdeletions in the common regions, similar to another commercial kit. Among the 58 male infertile patients, 7 (12.1%) had microdeletions of the Yq. Among the idiopathic azoospermic (n=22) and oligozoospermic (n=3) patients, 3 (12.0%) had microdeletions. Further, 2 of 21 varicocele patients (9.5%), 1 of 4 patients with testicular failure, and 1 patient with a 45,X/46,XY mosaic had microdeletions.

CONCLUSIONS

The kit was effective for detecting microdeletions of the Yq. We identified microdeletions in 12% of the infertile patients. This Y chromosome microdeletion detection kit is useful for screening Yq microdeletions in infertile patients.

The significance of Y chromosome microdeletion analysis in subfertile men with clinical variocele

INTRODUCTION

The aim of study is determining the cost-effectiveness of detection analysis in the presence of exceptional patients who have mild semen disorders, and beware of unnecessary varicocele repairs; and to ascertain whether patients with clinical varicocele should undergo Y chromosome (Yq) microdeletion analysis as a routine procedure.

MATERIAL AND METHODS

Varicocele with reflux was diagnosed in 51 male patients with subfertility symptoms upon physical examination (PE), confirmed by scrotal colour-Doppler ultrasound (CDU). After cytogenetic examination, Yq microdeletion analysis was performed on the peripheral blood samples using Promega Y Chromosome Deletion Detection System Version 2. Varicocele repair was performed under general anaesthesia with optical magnification (3-fold) through a subinguinal approach.

RESULTS

The mean age of the patients was 27.9. Values of semen concentration ranged from 0 to 72 million/ml, motility from 0 to 65% (A + B) and Kruger from 0% to 18%. The PE revealed normal size and consistency in the bilateral testicles. All patients were cytogenetically normal. However, Yq microdeletion was detected in 2 patients, 1 with mild oligoteratozoospermia and partial AZFb deletion (sY121) and the second patient with severe oligozoospermia and partial AZFc deletion (sY254 and sY255), and they were not subjected to varicocelectomy.

CONCLUSIONS

The routine performance of pre-operative Yq microdeletion analysis in patients with clinical varicocele does not seem to be cost-effective but the omission of patients with mild oligozoospermia would have subjected them to an unnecessary varicocelectomy and/or further ICSI applications and also would have caused the failure of referral for genetic counselling.

Cytogenetic abnormalities in 179 cases with male infertility in Western Region of Turkey: report and review

PURPOSE

In this study we aimed to evaluate the postnatally screened karyotype results in couples who were referred because of primary infertility between 2000 and 2006 in Izmir.

METHODS

The records of a total of 179 cases were evaluated retrospectively.

RESULTS

A total of 21 cases (11.74%) showed chromosomal alteration. Thirteen (7.26%) were 47,XXY; three (1.68%) were pericentric inversion of chromosome 9; one (0.56%) 46,XY/45,XO; one (0.56%) 46,XY/47,XXY/48,XXXY; one (0.56%) 46,XY,t(X;1); one (0.56%) 46,XY/46,XY,del(Y)(q11.2) and one (0.56%) 46,XX.

CONCLUSIONS

The rate of gonosomal chromosomal abnormalities was nearly three times higher in our region than the rate in the literature. Chromosomal analysis is strongly suggested particularly in those who suffer fertility problems.

Clinical consequences of microdeletions of the Y chromosome: the extended Münster experience

A total of 3179 patients were screened for Y-chromosome microdeletions and 821 patients for partial AZFc deletions. Thirty-nine Y-chromosomal microdeletions were found (2.4% of men with <1 x 10(6)/ml spermatozoa): two AZFa, two AZFb, one AZFbc, one partial AZFb, one partial AZFb+c and 32 AZFc (b2/b4). Partial AZFc deletions were found in 45 patients (5.5%), mostly gr/gr deletions (n = 28). In patients with AZFc deletion, azoospermia was found in 53.1% and sperm concentrations of mostly <0.1 x 10(6)/ml were found in 46.9%. Semen analyses and FSH measurements showed no trend over time. Elongated spermatids were seen in 6/15 AZFc patients and bilateral Sertoli cell-only was found in 4/15. Testicular sperm extraction (TESE) was attempted in 10 patients and spermatozoa were found in six. Compared with infertile men matched by sperm concentration, no differences in hormonal and seminal parameters could be found in patients with AZFc or gr/gr deletions. It is concluded that: (i) frequency of AZF deletions in Germany is much lower than in other countries; (ii) AZFc deletions are associated with severe disturbances of spermatogenesis and TESE is not possible in half of these patients; (iii) AZFc and gr/ gr deletions are not associated with any clinical diagnostic parameter; (iv) and no trend is apparent over time.

Rapid multiplexing and simultaneous detection of human spermatogenetic failure with a 12 lane microchip electrophoresis system

For the amplification and ultrafast separation of the genetic markers and DNA sequences that are related to human male infertility, a multiplex PCR for amplifying three DNA sequence-tagged sites (STS) located on the human Y chromosome with possible roles in the spermatogenesis process has been designed and applied followed by separation on a microchip. First, the optimum T(m) degree for the three DNA markers was optimized and determined experimentally, and the three DNA STS were amplified. These three DNA markers were then separated on a 12-lane microchip electrophoresis system, which can analyze the DNA markers on 12 channels simultaneously. The combination of these two technologies, multiplex PCR and microchip electrophoresis, allows the analysis of 36 DNA markers (12x3) within only 180 s.

Y chromosome microdeletions in infertile men with idiopathic oligo- or azoospermia

About 30-40% of male infertility is due to unknown reasons. Genetic contributions to the disruption of spermatogenesis are suggested and amongst the genetic factors studied, Y chromosome microdeletions represent the most common one. Screening for microdeletions in AZFa, b and c region of Y chromosome showed a big variation among different studies. The purpose of this study was to investigate the prevalence of such deletions in Saudi men. A total of 257 patients with idiopathic oligo- or azoospermia were screened for Y chromosome microdeletions by 19 markers in AZF region. Ten (3.9%) patients had chromosomal rearrangements, six of them showed sex chromosome abnormalities and four patients had apparently balanced autosomal rearrangements. Eight of the remaining 247 patients (3.2%) with a normal karyotype and no known causes of impaired spermatogenesis had Y chromosome microdeletions. Among these, six patients had deletions in AZFc region, one case had a deletion in AZFb and another had both AZFa and AZFc deletions.In conclusion, our study shows that Y chromosome microdeletions are low in our population. We also report for the first time a case with unique point deletions of AZFa and AZFc regions. The lower frequency of deletions in our study suggest that other genetic, epigenetic, nutritional and local factors may be responsible for idiopathic oligo- or azoospermia in the Saudi population.

Ultrafast diagnosis of the genetic-related disorders using the combined technologies of multiplex PCR and multichannel microchip electrophoresis

For the diagnosis of unexplained male infertility a multiplex PCR for 6 markers, which are well-known as candidate genes for studying male infertility and located on the human Y-chromosome, has been designed. The multiplex PCR products have been separated on a 12 channel microchip electrophoresis system, which can analyze different samples simultaneously. By combining the technologies of multiplex PCR with multichannel microchip electrophoresis, the number of the DNA markers that can be screened simultaneously is increased to be 72 marker (12 x 6) in a single run while the electrophoresis analysis time is reduced to be only 180 s.

Y chromosome microdeletions: are they implicated in teratozoospermia?

BACKGROUND

Y chromosome microdeletions are known to impair spermatogenesis. Screenings for these microdeletions are performed mostly in patients with sperm count abnormalities.

METHODS

We have screened the Y chromosome of 80 infertile patients with sperm morphological abnormalities. DNA from sperm, peripheral blood or single sperm following multiple displacement amplification (MDA) was utilized to amplify 20 specific sequence-tagged sites (STS) by PCR.

RESULTS

Y chromosome microdeletions were detected in sperm DNA from four of the teratozoospermic patients; while none of the 53 men with normal sperm morphology had any deletions. Two of the four patients with deletions also provided peripheral blood and a fresh semen sample. Both patients had none of the STS deleted in the peripheral blood DNA. Y chromosome microdeletion analysis in the MDA amplified SRY-positive single sperm DNA confirmed the presence of the same deletion in all 10 sperm for one patient and eight out of 10 sperm in the second patient.

CONCLUSIONS

Our observations suggest that some of the teratozoospermia might be related to gonadal mosaic Y chromosome microdeletions. Gonadal mosaicism can be a source of de novo transmissions of Y chromosome microdeletions. The application of MDA can yield enough DNA from a single sperm for genetic analyses.

Prevalence of chromosome defects in azoospermic and oligoastheno-teratozoospermic South Indian infertile men attending an infertility clinic

The prevalence of chromosomal abnormalities in azoospermic and oligoastheno-teratozoospermic infertile men of South Indian origin undergoing assisted reproductive technologies was evaluated. In addition, the study aimed to investigate new abnormal karyotypes involving autosomes in azoospermia and sex chromosomes in oligoastheno-teratozoospermic individuals that are supposed to be rare. Metaphase chromosomes of 744 infertile men, including 272 men with azoospermia and 472 men with oligoastheno-teratozoospermia (OAT), were analysed using Giemsa-trypsin-Giemsa banding and fluorescence in-situ hybridization (FISH) wherever necessary. Chromosomal abnormalities were observed in 59 (7.9%) individuals of the total studied population. Among these, 30 out of 272 (11.0%) azoospermic men and 29 out of 472 (6.1%) infertile men with OAT showed chromosomal abnormalities. A strong and statistically significant association (OR = 1.89; P = 0.0235) of chromosomal abnormalities and sex chromosome abnormalities (OR = 4.29; P = 0.001) with azoospermia when compared with OAT was observed. In addition, six autosomal abnormalities associated with azoospermia and two abnormalities involving Y chromosome, which include a novel karyotype (mos 46,XY/51,XYYYYYY) in OAT individuals, were detected.