Inbreeding is associated with lower 2D: 4D digit ratio

@article{zener2014InbreedingIA,
  title={Inbreeding is associated with lower 2D: 4D digit ratio},
  author={Barış {\"O}zener and Peter L. Hurd and Izzet Duyar},
  journal={American Journal of Human Biology},
  year={2014},
  volume={26}
}
While consanguineous marriage has been shown to result in a small increase in risk of recessive Mendelian disorders among offspring, far less research has been conducted on the effects of inbreeding on complex traits. These effects, thought to result from increased developmental instability due to loss of heterozygosity, are expected to be found more pervasively than rare recessive Mendelian traits and are expected to result in increased developmental noise. Here, we test for a direct effect of… 
Relationship between parental consanguinity and digit ratios (2D:4D) among Turkish newborns in Sivas
The aim of this study was to investigate the effects of parental consanguinity on the 2D:4D digit ratio of newborn infants, whose parents were the first cousins.
TÜRKİYE FİZİKSEL ANTROPOLOJİ ÇALIŞMALARI BİBLİYOGRAFYASI (1930-2014)
Bu makalede, Antropoloji egitimlerini Turkiye’de yapmis olan arastirmacilarin Fiziksel Antropoloji konusunda calismalarinin bibliyografyasi verilmistir. Bu calismalar antropometri, ergonomi, obezite,
Hadza hunter-gatherer men do not have more masculine digit ratios (2D:4D).
TLDR
These findings challenge the current view that lower 2D:4D in men is a uniform characteristic of the authors' species and may be related to known patterns of hormonal variation resulting from both genetic and environmental mechanisms.

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