Extra chromosome doesn’t lead to early death

DEAR DR. DONOHUE: I have Klinefelter's syndrome. I have information that unless you take testosterone before you hit 30, you'll never make it past 30. I am 34 and am the oldest person living with this syndrome. D.N.

ANSWER: Chromosomes are long strands of genes. Each of us has 46. Half come from the mother and half from the father. Two of those chromosomes determine a person's sex. A woman has a pair of XX chromosomes; a man has XY sex chromosomes.

In Klinefelter's syndrome, the baby is born with three sex chromosomes: XXY. (There are variations on this combination.) The infant looks like and is raised as a boy.

Often, overt signs of the syndrome aren't recognized until puberty, and sometimes they are never recognized. They can be quite subtle. Many Klinefelter's children have difficulty learning. They often are not as coordinated as their peers. At puberty, the testes fail to grow. Most are infertile. Facial and chest hair is scanty. These boys are tall but have poor muscle development. The breasts may enlarge.

When the syndrome is recognized early, the male hormone testosterone is started around age 12 and promotes typical male features. It can even be given much later if there is a delay in recognizing the syndrome.

Klinefelter's syndrome does not cause death at an early age. That is a piece of misinformation someone has fed you.

You can obtain valuable information on this condition by connecting with the Klinefelter Syndrome and Associates Web site, at www.genetic. org.

Dr. Donohue regrets that he is unable to answer individual letters, but he will incorporate them in his column whenever possible. Readers may write him or request an order form of available health newsletters at P.O. Box 536475, Orlando, FL 328536475.