The costs of human inbreeding and their implications for variations at the DNA level

@article{Bittles1994TheCO,
  title={The costs of human inbreeding and their implications for variations at the DNA level},
  author={Alan H. Bittles and James V. Neel},
  journal={Nature Genetics},
  year={1994},
  volume={8},
  pages={117-121}
}
An analysis of the world literature on the children of first cousin marriages reveals that the depression of survival in offspring followed from birth (including late miscarriages; at about six months gestation or later) to a median age of 10 years is constant (4.4% ± 4.6) across a wide range of values for population prereproductive mortality. There is thus no evidence for the action of conditional lethals. On the basis of these data, it is calculated that the average human is heterozygous for… 

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...

References

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