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. 2020 Sep 23;10(1):15573.
doi: 10.1038/s41598-020-72366-z.

The structure of first-cousin marriages in Brazil

Paulo A Otto  1 , Renan B Lemes  1 , Allysson A Farias  1 , Mathias Weller  2 , Shirley O A Lima  2 , Victor Alves Albino  2 , Yanna K Marques-Alves  2 , Eliete Pardono  1 , Magnolia A P Bocangel  1 , Silvana Santos  3
Affiliations

The structure of first-cousin marriages in Brazil

Paulo A Otto et al. Sci Rep. .

Abstract

This paper deals with the frequency and structure of first-cousin marriages, by far the most important and frequent type of consanguineous mating in human populations. Based on the analysis of large amounts of data from the world literature and from large Brazilian samples recently collected, we suggest some explanations for the asymmetry of sexes among the parental sibs of first-cousin marriages. We suggest also a simple manner to correct the method that uses population surnames to assess the different Wright fixation indexes FIS, FST and FIT taking into account not only alternative methods of surname transmission, but also the asymmetries that are almost always observed in the distribution of sexes among the parental sibs of first-cousins.

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Conflict of interest statement

The authors declare no competing interests.

Figures

Figure 1
Figure 1
Subtypes of first-cousin marriages (see text for details).
Figure 2
Figure 2
Distribution of a = A/N and d = D/N values in the samples described on Table 1, identified by the figures shown at the leftmost column of this table.
Figure 3
Figure 3
Distribution of a = A/N and d = D/N values in the Brazilian samples (see details and explanations on the text above).
Figure 4
Figure 4
Indication of a negative correlation between the frequency of consanguineous mating and population sizes in the state of Paraiba in NE Brazil (data taken from Weller et al.). The black line corresponds to the regression line of the data.
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References

    1. Freire Maia N. Consanguineous marriages in Brazil. Eugen. Quart. 1958;5:105–114. doi: 10.1080/19485565.1958.9987358. - DOI
    1. Freire-Maia N, Freire-Maia A. The structure of consanguineous marriages and its genetic implications. Ann. Hum. Genet. 1961;25:29–39. doi: 10.1111/j.1469-1809.1961.tb01494.x. - DOI - PubMed
    1. Otto, P. A. & Lettieri, F. Subtipos de casamentos entre primos em primeiro grau. in Livro da 44a Reunião Anual da Soc. Bras. Progr. Ciência. 801 (Soc. Bras. Progr. Ciência., 1992).
    1. Otto, P. A., Frota-Pessoa, O. & Vieira-Filho, J. Genetic risks of consanguineous marriages. in Fifty years of human genetics: A Festschrift and liber amicorum to celebrate the life and work of George Robert Fraser. (eds. Mayo, O. & C., L.) 436–442. (Wakefield Press, 2007).
    1. Martello, N. Os efeitos diferenciais da consanguinidade nos dois sexos. (Universidade de São Paulo, 1967).