To Your Good Health: Commercial lab tests versus genetic counseling

I have a daughter, almost 31 years old, who is concerned about Charcot-Marie-Tooth syndrome. Her maternal grandmother has been diagnosed with that condition. She is interested in seeking out a genetic test for the condition to learn if she is susceptible. She was referred to a commercial, direct-to-consumer laboratory for the test. How likely is it that a lab test for this specific condition would be accurate? Should she be doing all of this through either a particular type of genetics counselor or her private physician, an internist, rather than an independent effort?

Charcot-Marie-Tooth disease is the eponym given to a family of hereditary motor sensory neuropathies, diseases that affect the nerves that carry the impulses necessary for movement and sensation. The initial symptoms are most commonly weakness and atrophy in the feet, followed by similar problems in the hands and sensory changes.

The diagnosis may be made by EMG testing — electromyography, a needle study of the electrical activity of the muscles — but genetic testing is another way of making the diagnosis. If her grandmother has a known mutation, then genetic testing is likely to give her confirmation of her own status.

Commercial genetic testing is certainly available and probably accurate. However, I would still recommend a visit to a genetic counselor. This may require a referral from her primary-care doctor.

The correct test to order, and its interpretation, depends on the exact diagnosis of her grandmother’s condition, since there are many genetic variations of Charcot-Marie-Tooth.

It is likely that your daughter will have questions after the test results, and the benefit of having an experienced clinician there to answer them would be invaluable.

I’m an 81-year-old man. About two years ago, I began to realize that my testicles were shrinking, and they are now about the size of a marble. I have asked my primary-care doctor and urologist about this, and the reply is that nothing can be done about it. I have read that boxer shorts are recommended to keep the testicles cooler and healthier. I am wondering whether my extensive time sitting at a desk and reading could be related to my shrinking testicles. Or, is it related to erectile dysfunction, which is caused by decreased blood flow? I have ED. My last testosterone result was about 500. Is there nothing that can be done, not even any exercises?

The medical term for what’s happening to you is “testicular atrophy,” and it has several possible causes. Age alone is one: At age 81, many men have noticed some shrinkage in testicular size, but yours is beyond the norm. You are right that cooler temperatures are healthier for the testicles, but again, I am a little surprised by the severity of your description.

Among the other common causes are a history of trauma or infection. However, any underlying cause can also affect the ability of the testicles to make testosterone.

Your blood testosterone level is surprisingly normal for your age; 400 to 500 is the average for a man in his 80s. A low testosterone is a common cause of erectile dysfunction. Poor blood flow is only one cause of ED.

After two years, it is very unlikely that any treatments will affect the testicles now, unfortunately.