One Man’s Sperm Reveals Clues to Fertility

Leslie Carol Botha:  I can still remember when problems with fertility and genetic defects in offspring were blamed on the woman.  I am glad to see that science is realizing the crucial role the health of the sperm has on conception. This is a very interesting article with many implications. I have heard so many stories from women struggling to get pregnant and they switch to a relationship with a man who is health conscious and they no longer have problems with their fertility.

Scientists Map Genomes of One Man’s Sperm

The pioneering work reveals clues to fertility, how DNA is mixed and passed on.

By E.J. Mundell, HealthDay Reporter
July 19, 2012 Health Day News
Scientists say they’ve mapped the entire genomes of 91 sperm from one man, the first time such gene mapping has been done in a human gamete (sperm or egg cell).
The research gives a glimpse into recombination — the process by which DNA mixes to create offspring that carry with them traits from parents and grandparents, the Stanford University scientists explained.

“We were able to generate an individual recombination map and mutation rate for each of several sperm from one person,” study co-author Barry Behr, director of Stanford’s in vitro fertilization laboratory, said in a university news release. “Now we can look at a particular individual, make some calls about what they would likely contribute genetically to an embryo, and perhaps even diagnose or detect potential problems.”

The findings were published July 20 in the journal Cell.

Until now, scientists had only been able look to population-wide studies to try and gauge how often recombination happened in sperm and eggs cells, and how complicated the process might be, the Stanford team stated.

The new study focused on the sperm of a healthy 40-year-old man who had normal sperm and had already fathered healthy offspring. The study found that prior population studies were fairly accurate in assessing rates of recombination.

The team reported that, as expected, the man’s sperm each had undergone about 23 recombinations of DNA, although there were wide variations in this genetic mixing between individual sperm. Two of the sperm sampled were missing entire chromosomes, the authors pointed out.

Between 25 and 36 “new single nucleotide mutations” were also spotted — random mutations that can affect offspring for good or ill.

PG

Author: Leslie Carol Botha

Author, publisher, radio talk show host and internationally recognized expert on women's hormone cycles. Social/political activist on Gardasil the HPV vaccine for adolescent girls. Co-author of "Understanding Your Mood, Mind and Hormone Cycle." Honorary advisory board member for the Foundation for the Study of Cycles and member of the Society for Menstrual Cycle Research.