Chromosomal Alterations and Male Infertility

Infertility is one of the most common disorders seen in medical practice worldwide. It is defined as the inability of a couple to conceive after 1 year of unprotected sexual intercourse. The number of infertile couples in the general population is increasing and the recent studies show that about 15 to 20 % of couples in their reproductive age are unable to have their own child is presenting an almost unsolvable challenge to the health service. Infertility is a problem of immense importance due to its social, emotional and religious nature. Furthers more it exhausts the couple psychologically, socially, and also drains their financial resources. [1,2].

Due to increased number of infertility centers, the diagnostic and therapeutic facilities are coming within the reach of these infertile couples and can be easily helped by the use of assisted reproduction techniques. Even, Intrauterine Insemination (IUI) and Intracytoplasmic Sperm Injection (ICSI) by using the donors semen has received tremendous acceptance by these infertile couples. The practice of using ICSI technique by these severely infertile men carries the risk of passing on genetic disorders to their children including chromosomal abnormalities [2,3].

Chromosomal abnormality is one of the important causes of male infertility because it disrupts genes which are involved in the genetic control of spermatogenesis can leads in to abnormal semen parameters like non- obstructive azoospermia or sever oligozoospermia with asthenozoospermia or teratospermia or both oligo-astheno-teratozoospermia. The most frequent chromosomal abnormalities found in infertile men are translocations and sex chromosome abnormalities. The impact of chromosomal abnormalities on male infertility is very high and inversely related to the sperm count. Major chromosomal abnormalities found with the range of 2.6 - 16.5 % in infertile men compared to the incidence in normal male population 0.3 - 0.4%; in which azoospermia are with high frequency from 11.6% - 23.8%, oligozoospermia the incidence is 2.3 - 6.6 % while in severe oligozoospermia it is about 10.4% [3,4,5]. Chromosomal abnormalities can be easily diagnosed after performing G banding using trypsin and Giemsa (GTG) karyotyping. Therefore, karyotyping study is definitely a mandatory test in the diagnostic center of any infertile male [5,6,7].

Polymorphic chromosomal variants also have been well studied both in the normal population and in infertile males. Polymorphic variations are known to occur in the general population. However, higher frequencies of these variants have recently been reported in infertile and subfertile individuals, compared with normal population. Increased rates of chromosomal polymorphic variants have been shown to be associated with poor spermatogenesis [6,7].

Therefore, the present study was undertaken to find out the frequency and types of chromosomal alterations; major chromosomal abnormalities and polymorphic chromosomal variants in infertile males and to show the importance of cytogenetic screening of such patients prior to the use of Assisted Reproduction Technique (ART), it is important to prevent them being passed on to their children. This is of particular importance when abnormalities are found in the Y chromosome, as they will be passed on to any male offspring.