Recombination rate and reproductive success in humans.
Intergenerational mixing of DNA through meiotic recombinations of homologous chromosomes during gametogenesis is a major event that generates diversity in the eukaryotic genome. We examined genome-wide microsatellite data for 23,066 individuals, providing information on recombination events of 14,140 maternal and paternal meioses each, and found a positive correlation between maternal recombination counts of an offspring and maternal age. We postulated that the recombination rate of eggs does not increase with maternal age, but that the apparent increase is the consequence of selection. Specifically, a high recombination count increased the chance of a gamete becoming a live birth, and this effect became more pronounced with advancing maternal age. Further support for this hypothesis came from our observation that mothers with high oocyte recombination rate tend to have more children. Hence, not only do recombinations have a role in evolution by yielding diverse combinations of gene variants for natural selection, but they are also under selection themselves.
Kong
Augustine
A
deCODE Genetics, Sturlugata 8, IS-101 Reykjavik, Iceland. kong@decode.is <kong@decode.is>
Barnard
John
J
Gudbjartsson
Daniel F
DF
Thorleifsson
Gudmar
G
Jonsdottir
Gudrun
G
Sigurdardottir
Sigrun
S
Richardsson
Bjorgvin
B
Jonsdottir
Jonina
J
Thorgeirsson
Thorgeir
T
Frigge
Michael L
ML
Lamb
Neil E
NE
Sherman
Stephanie
S
Gulcher
Jeffrey R
JR
Stefansson
Kari
K
D000293:Adolescent; D000328:Adult; D005191:Family Characteristics; D005260:Female; D006801:Humans; D008297:Male; D008423:Maternal Age; D018895:Microsatellite Repeats; D008875:Middle Aged; D010331:Paternal Age; D011995:Recombination, Genetic; D012098:Reproduction / Q000235:genetics*; D012641:Selection, Genetic