Tuesday, 1 January, 2008

Zero Sperm Counts & Genetic Links

What has become evident at our Centers over the last several years is that our ability to diagnose and successfully treat severe male infertility problems has surpassed our ability to understand the basic causes of these problems. In the recent past, it was considered that nearly 20% of men with extremely low or "zero" sperm counts had no known medical reason for their fertility problems. Most recently, major advances in molecular biology and genetics have provided the "reasons" for severe infertility (very low or zero sperm counts) in many men whose fertility problems were previously poorly understood. We now know that 20-30% of men with such low (under 10 million/ml) or zero sperm counts have a now identifiable genetic cause for their problem. While we are now able to assist many, many men previously thought to be "hopelessly" infertile achieve pregnancy, it remains very important to not only treat these men, but to provide such couples with genetic information related to the problem causing the low or zero count. This is important because many of these genetic characteristics may potentially be passed along to children conceived with the help of modern male infertility treatments. Genetic disorders that would previously not have been able to be "passed along" due to the male's infertility are now being retained in the "gene pool" as a result of new procedures that overcome most of these previously untreatable male conditions.
Y chromosome deletions can be a contributing factor in male infertility. Only men have a Y chromosome and it is passed from father to son. The Y chromosome contains genes that direct an embryo to develop into a male. While there are few genes on the Y chromosome, included are genes that are important for male fertility.Microdeletions are missing regions of DNA that are so small they can't be detected through normal chromosome analysis. Instead, labs use advanced techniques like polymerase chain reaction (PCR) to detect whether the regions are present or missing. Sperm production is affected when there are microdeletions on the long arm of the Y chromosome in regions called AZF (for azoospermic factor). Genetic testing looks at three AZF regions. If a deletion is found, the prognosis depends on the amount of missing DNA and the region in which it is missing. Y chromosome microdeletions are the second most common genetic reason that men have a low sperm count or lack sperm. (Klinefelter's syndrome is the most common reason.) Currently, there are no other known health problems that come from having a Y chromosome microdeletion other than infertility.
Incidentally, we were the first in India to offer this test. You can order this test from our homepage at http://www.iwannagetpregnant.com/myctest.shtml
Wishing our bloggeurs a fertile new year!

1 comment:

Anonymous said...

what's the cost of Y chromosome microdeletion test?
Should it be offered to all the patients having low sperm counts?What r the chances of passing it on to the offspring and what is treatment offered to such males that they do not pass it to future generations?