Clinical and laboratory evaluation of idiopathic male infertility in a secondary referral center in India

Abstract

The genetic basis of infertility has received increasing recognition in recent years, particularly with the advent of assisted reproductive technology. It is now becoming obvious that genetic etiology for infertility is an important cause of disrupted spermatogenesis. Y-chromosome microdeletions and abnormal karyotype are the two major causes of altered spermatogenesis. To achieve biological fatherhood, intracytoplasmic sperm injection (ICSI) is performed in cases of severe infertility with or without genetic abnormalities. There is a concern that these genetic abnormalities can be transmitted to the male progeny, who may subsequently have a more severe phenotype of infertility. A total of 200 men were recruited for clinical examinations, spermiograms, hormonal profiles, and cytogenetic and Yq microdeletion profiles. Testicular biopsy was also performed whenever possible and histologically evaluated. Genetic abnormalities were seen in 7.1% of cases, of which 4.1% had chromosomal aberrations, namely Klinefelter's mosaic (47XXY) and Robertsonian translocation, and 3.0% had Yq microdeletions, which is very low as compared to other populations. Follicle stimulating hormone (FSH) and luteinizing hormone (LH) were significantly increased in men with nonobstructive azoospermia (NOA) as compared to severe oligoasthenozoospermia (Po0.0001), whereas testosterone levels were significantly decreased in men with microdeletions as compared to men with no microdeletions (Po0.0083). Low levels of androgen in men with microdeletions indicate a need to followup for early andropause. Patients with microdeletions had more severe testicular histology as compared to subjects without deletions. Our studies showed a significant decrease (Po0.002) in the serum inhibin B values in men with NOA, whereas FSH was seen to be significantly higher as compared to men with severe oligoasthenozoospermia (SOAS), indicating that both the Sertoli cells as well the germ cells were significantly compromised in cases of NOA and partially affected in SOAS. Overall inhibin B in combination with serum FSH would thus be a better marker than serum FSH alone for impaired spermatogenesis. In view of the genetic and hormonal abnormalities in the group of infertile men with idiopathic severe oligozoospermia and NOA cases, who are potential candidates for ICSI, genetic testing for Y-chromosome microdeletions, karyotype, and biochemical parameters is advocated.

Association of progesterone receptor gene polymorphism with male infertility and clinical outcome of ICSI

“…Testing for Yq microdeletions was done by PCR using six pairs of STS primers that span the azoospermic factor (AZFa, AZFb and AZFc) loci. The primers and the method for STS PCR has been detailed elsewhere [1,2,35]. Individuals with karyotype abnormalities or Yq microdeletions were excluded from the study.…”

“…The sequences for the same are shown in supplementary Table 1. PCR was performed at an optimized annealing temperature and has been detailed elsewhere [1,5,40]. The amplicons were further subjected to direct sequencing [5,40] using BigDye Terminator cycle sequencing kit (Applied Biosystems, Foster City USA) and 3730 DNA analyzer (Applied Biosystems).…”

“…Microdeletions on the long arm of the Y chromosome (Yq), encompassing critical genes involved in spermatogenesis, has been observed in 5-10 % of infertile men [1,14,26,35]. In addition, mutations/polymorphisms in several autosomal genes have been identified in a subset of individuals with male factor infertility [15,26].…”

Susceptibility of gr/gr rearrangements to azoospermia or oligozoospermia is dependent on DAZ and CDY1 gene copy deletions

“…A biplex PCR amplification using the standard sequence tagged site (STS) primer pair for sY1291/sY1191 along with SRY as the endogenous housekeeping control gene was performed. The amplification reactions were carried out using Red Amp (2X) PCR master mix (Sigma-Aldrich, St Louis., USA) for 35 cycles as detailed previously [2,4,6]. The primer sequences, optimized annealing temperatures and expected PCR product size are given in Supplementary Table. I.…”

“…Microdeletions involving the Azoospermia Factor loci (AZF) on the long arm of the Y chromosome (Yq) are a genetic cause of male infertility and the deletions of the AZFa, AZFb or AZFc loci alone or in combination occur in 2-10 % of men with abnormal seminogram [2][3][4][5][6]. Since Yq microdeletions can be vertically transmitted to the male offspring born after assisted reproduction [7,8], screening for these microdeletions has become a part of the routine diagnostic workup for men with azoospermia or oligozoospermia [5].…”