After picking from the previous entry, we found out that unlike in women, the researchers found no correlation between male aging and chromosome changes that cause Down’s syndrome and other forms of trisomies – such as Klinefelter syndrome, Turner syndrome, triple X syndrome, and XYY in offspring – that are associated with varying types and severity of infertility as well as physical and neurological abnormalities. They did conclude, however, that some older men could be at risk for fathering children with dwarfism, and that “a small fraction of men are at increased risks for transmitting multiple genetic and chromosomal defects.”
In the case of Apert syndrome, a serious disfiguring birth defect, the researchers found that the effects of advancing male age may differ among different groups of men. Apert syndrome gene mutations increased in the sperm of a second group of men recruited in the Baltimore inner city by researchers at Johns Hopkins Medical Center, while no age effects were observed in the group of men recruited in California.
Wyrobek noted that these differences in finding suggest that factors other than age may be involved, raising the possibility that socioeconomic or dietary factors or ethnic background may also be involved in how age affects the quality of human sperm.
“Since some forms of genomic damage change with age and others don’t,” he said, “overall genomic sperm quality cannot be measured by any single sperm test.”
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