Dad’s sperms have role in embryo development
June 20, 2009 by Grace Ibay
Filed under Health
The elementary concept is that the father’s role in making babies is to only contribute the sperm, and the mother does all the work. That after fertilization, the development of the resulting embryo is at the mercy of the mother’s egg cytoplasm that received it.
Well, recent studies show that dad’s sperm contains a set of instructions that make certain the embryo develops properly, and specifically that his genes get turned on at the right time.
But let’s do a short tutorial first…
Each chromosome is really just a single long DNA molecule, that can stretch out to an average 1 meter long. Those 23 long strands of human DNA must be packaged and coiled into a tiny nucleus. The proteins responsible for packaging them are called histones. Histone molecules repeatedly fold and coil the DNA strand into the more visible (through microscope) chromosome. Histones also regulate which portions of the DNA can unravel so that genes can be replicated and expressed at the right timing for the embryo to develop normally. Histones are also highly conserved in evolution, meaning they are identical from one organism to another and likely have the same functions in all organisms.
A new study published at Nature found that specially-modified histones are strategically found in different areas of the sperm chromatin. In some areas, the father’s genes that need to be turned on early in an embryo’s development are marked with modified histones different from those genes that are needed later in the development.
What’s the implication for this finding? Bradley R. Cairns, senior researcher of the team, remarked that a man’s age and lifestyle could affect the sperm chromatin in such a way that impacts fertility or development of the embryo. Cairns also expressed hope that a diagnostic test could be developed based on his results that will help couples with fertility issues.
Read more about the study in “Sperm’s Genes Packaged with Instructions for Development”.
Image: Newscom
The current study says that from the National Health Interview Surveys, both of which included supplementary questions assessing cancer control. More than 35,000 women participating in those surveys did not have a personal history of breast or ovarian cancer, and around 1 percent of them were determined to be at high risk because a mother, sister, or daughter had such a tumor.