View Full Version : Estrogen Wars: 1) Fewer Eggs, 2) Quirky Males

James Brody
February 21st, 2007, 05:23 PM
The male-female arm-wrestling occurs in arenas beyond Harvard Yard. And this piece could have been targeted on epigenetics and gene-environment interactions!

1) Some magic stuff in soy is associated with reduced female reproductive performance. And there are spooky linkages to reports the development of breasts in adolescent males who used estrogen-fortified shampoos. Did they also have mothers who fed them on soy? And is soy a player in the IQ and social habits in Oriental cultures? Does soy have a role in the IQ differences reported to exist between Orientals and Caucasians?

2) There is greater variation in epigenetic mutations in males with old sperm. Small wonder that guys are developmentally more varied and are more apt to be thieves and saints, imbeciles and geniuses. And the profound truth: estrogen may be a key player in the emergence of K-selection as females, human or not and in stable environments, produce fewer children generally but (possibly) with the same range of variation in male characteristics. That is, there may be fewer guys but we may be just as bizarre as the prior generation when there were more of us. And females remain alert to separate the tolerable fools, criminals, and perverts from the intolerable ones.

Female Fecundity

1) Reference:

Dolinoy et al (2006) Genistein regulates the fetal epigenome. Environ Health Perspect. 114:567-572.

"Genistein, the major phytoestrogen in soy, is linked to diminished female reproductive performance and to cancer chemoprevention and decreased adipose deposition... The extent of DNA methylation was similar in endodermal, mesodermal, and ectodermal tissues, indicating that genistein acts during early embryonic development...A number of important implications result from these findings.

"Firstly, they demonstrate that it is essential to determine the effects of environmental factors on the epigenome during prenatal and early postnatal development, rather than just in adults.

"Secondly, since phytoestrogen content in laboratory animal feed is highly variable, genistein's effect on fetal DNA methylation patterns could significantly influence the interpretation of hormone and other rodent assay studies as well as confound the interpretation of gene expression arrays and DNA methylation studies.

"Finally, it needs to be determined if the relatively high genistein intake of infants consuming soy formulas is beneficial or has unintended deleterious effects on the human epigenome, especially in the United States and other countries where the food supply is fortified with folic acid."

Estrogen Wars: Male Variation

2) Reference
Rivka L. Glaser, and Ethylin Wang Jabs (2004) Dear Old Dad. Sci. Aging Knowl. Environ., 21 January.
"Abstract: The origin and frequency of spontaneous mutations that occur with age in humans have been a topic of intense discussion. The mechanisms by which spontaneous mutations arise depend on the parental germ line in which a mutation occurs. In general, paternal mutations are more likely than maternal mutations to be base substitutions. This is likely due to the larger number of germ cell divisions in spermatogenesis than in oogenesis. Maternal mutations are more often chromosomal abnormalities. Advanced parental age seems to influence some mutations, although it is not a factor in the creation of others. In this review, we focus on patterns of paternal bias and age dependence of mutations in different genetic disorders, and the various mechanisms by which these mutations arise. We also discuss recent data on age and the frequency of these mutations in the human male germ line and the impact of these data on this field of research."