Y choromosomal microdeletion screening in the workup of male infertility and its current status in India

Spermatogenesis is an essential stage in human male gamete development, which is regulated by many Y chromosome specific genes. Most of these genes are centred in a specific region located on the long arm of the human Y chromosome known as the azoospermia factor region [AZF]. Deletion events are common in Y chromosome because of its peculiar structural organization. Astonishingly, among the several known genetic causes of male infertility, Y chromosomal microdeletions emerged as the most frequent structural chromosome anomaly associated with the quantitative reduction of sperm. The development of assisted reproductive techniques [ART] like intra-cytoplasmic sperm injection [ICSI] and testicular sperm extraction [TESE] helps to bypass the natural barriers of fertilization, but it increases the concern about the transmission of genetic defects. Experimental evidence suggested that the men with Y chromosomal microdeletions vertically transmitted their deletion as well as related fertility disorders to their offspring via these ART techniques. In India, infertility is on alarming rise. ART centres have opened up in virtually every state but still most of the infertility centres in India do not choose to perform Y chromosomal microdeletion diagnosis because of some advanced theoretical reasons. Moreover, there is no consensus among the clinicians about the diagnosis and management of Y chromosomal microdeletion defects. The current review discusses thoroughly the role of Y chromosome microdeletion screening in the workup of male infertility, its significance as a diagnostic test, novel approaches for screening Y deletions and finally a systematic review on the current status of Y chromosome microdeletion deletion screening in India

Multiplex PCR based screening for microdeletions in azoospermia factor region of Y chromosome in azoospermic and severe oligozoospermic south Indian men

Y chromosomal microdeletion is an important genetic disorder, which may arise due to intrachromosomal recombination between homologous sequences in the male specific region of the human Y chromosome. It is frequently associated with the quantitative reduction of sperm. The screening for Y chromosomal microdeletions has a great clinical value. To develop a sequence tagged site [STS] based multiplex PCR protocol, which could be specific for the rapid detection of AZF deletions and thereby estimating the frequency of AZF sub deletions in infertile South Indian men. In the current study, PCR based Y chromosomal microdeletion screening analysis was performed in 75 men including 30 non-obstructive azoospermic men, 20 severe oligozoospermic, and 25 normozoospermic fertile men [controls] using 15 known STS primer pairs mapped within the AZF locus. Deletion frequency was estimated after successful PCR amplification. We designed and optimized a STS based multiplex PCR protocol, which could be helpful for the clinicians to detect the Y chromosomal deletions rapidly and specifically. In our study, we estimated an overall deletion frequency of 36%. Among these 12 [40%] were azoospermic and 6 [30%] were oligozoospermic. No microdeletions were observed in normozoospermic fertile men. Our Study emphasizes the fact that Y chromosomal microdeletion screening tests are unavoidable in the workup of idiopathic male infertility. Mandatory screening for Y deletions should be done in all azoospermic and severe oligozoospermic patients before undergoing assisted reproductive technology