When many of us hear of someone with low testosterone (or low T), we tend to think of someone in his retirement years. We picture a grey-haired man with a low sex drive and erectile dysfunction. However, this does not happen overnight. Some people may have had this since before birth and do not even know it.
Scientists now believe low testosterone is hereditary, and have been able to pinpoint genetic markers for it. In fact, men with three or more of these markers are almost seven times likely to have low testosterone, versus men with no markers. The majority of the markers were found in the sex hormone-binding globulin gene. It is a type of protein that binds to testosterone. An increase of this protein can lead to a decrease of testosterone.
Klinefelter is the first possible genetic disorder that can cause low levels of testosterone. A male normally has one X chromosome and one Y chromosome. With Klinefelter’s, there are two or more X chromosomes, along with the Y chromosome. It is not a hereditary condition. It is due to an error during conception. This leads to abnormal development of the testicles, and in turn, low levels of testosterone. Men who have this have enlarged breasts, reduced body hair, and lower body masses. It is not unusual adults for with minimal symptoms to be unaware that the syndrome until they are tested for infertility. They are, usually, capable of normal sexual function but have almost no sperm count. However, all is not lost. Fertility treatments are available for men who want to have children.
Kallmann is also an X-linked chromosome disorder. In this case, the hormones LH and FSH are impaired, which in turn, decrease the amount of testosterone. This disorder affects both men and women, but is seen more in men. Both sexes fail to start or entirely complete puberty. Moreover, men’s testicles tend to be smaller, and like those with Klinefelter syndrome, fertility treatment is available.
Prader-Willi syndrome occurs because of an error with chromosome 15. For example, some of the paternal genes are missing, and two copies of that chromosome were inherited from the mother and none from the father, or there is some defect in the paternal genes. Both sexes are again affected. Testes in men and ovaries in women produce little or no sex hormones, which means incomplete development at puberty and infertility. Without treatment, women may not start menstruating until their 30s, or they may never have a period. Men may not have much facial hair, and their voices may never fully deepen. Interestingly, people with Prader-Willi may always be hungry, eating large quantities of food. They may even consume garbage.
Finally, there is Myotonic dystrophy – the most common adult form of muscular dystrophy. It occurs in men and is carried on the Y chromosome; because testicular failure, usually, occurs around the age of 30 to 40, men may have sons at risk for the disease.
If you suspect you suffer for low T, see your doctor so he or she can do a workup. Providing a physician with a detailed medical history will help the process. The doctor will ask questions about past or current illnesses, medications, family diseases and sexual issues. A physical exam will also be performed. The doctor will look at body hair and the size of genitalia while looking for lumps. A simple blood test will also be conducted. Some diagnostic tests, such as an X-ray or MRI, may also be done. If a genetic cause is suspected, DNA testing will be performed. Regardless of the cause however, always remember that FDA-approved testosterone treatments are available: so you don’t have to merely settle for what nature has handed you.