Tag Archives: jumping genes

Fertility: Sacrificing eggs for the greater good

A woman’s supply of eggs is a precious commodity because only a few hundred mature eggs can be produced throughout her lifetime and each must be as free as possible from genetic damage. Part of egg production involves a winnowing of the egg supply during fetal development, childhood and into adulthood down from a large starting pool. New research by Carnegie’s Alex Bortvin and postdoctoral fellow Safia Malki have gained new insights into the earliest stages of egg selection, which may have broad implications for women’s health and fertility. The work is reported in the early on-line edition of Developmental Cell. (more…)

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A “Jumping Gene’s” Preferred Targets May Influence Genome Evolution

Baltimore, MD — The human genome shares several peculiarities with the DNA of just about every other plant and animal. Our genetic blueprint contains numerous entities known as transposons, or “jumping genes,” which have the ability to move from place to place on the chromosomes within a cell.

An astounding 50% of human DNA comprises both active transposon elements and the decaying remains of former transposons that were active thousands to millions of years ago before becoming damaged and immobile. If all of this mobile and formerly mobile DNA were not mysterious enough, every time a plant, animal or human cell prepares to divide, the chromosome regions richest in transposon-derived sequences, even elements long deceased, are among the last to duplicate. The reason for their delayed duplication, if there is one, has eluded biologists for more than 50 years. (more…)

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