iBet uBet web content aggregator. Adding the entire web to your favor.
iBet uBet web content aggregator. Adding the entire web to your favor.



Link to original content: http://pubmed.ncbi.nlm.nih.gov/21687665/
Twin Town in South Brazil: a Nazi's experiment or a genetic founder effect? - PubMed Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2011;6(6):e20328.
doi: 10.1371/journal.pone.0020328. Epub 2011 Jun 8.

Twin Town in South Brazil: a Nazi's experiment or a genetic founder effect?

Alice Tagliani-Ribeiro  1 , Mariana Oliveira, Adriana K Sassi, Maira R Rodrigues, Marcelo Zagonel-Oliveira, Gary Steinman, Ursula Matte, Nelson J R Fagundes, Lavinia Schuler-Faccini
Affiliations

Twin Town in South Brazil: a Nazi's experiment or a genetic founder effect?

Alice Tagliani-Ribeiro et al. PLoS One. 2011.

Abstract

Cândido Godói (CG) is a small municipality in South Brazil with approximately 6,000 inhabitants. It is known as the "Twins' Town" due to its high rate of twin births. Recently it was claimed that such high frequency of twinning would be connected to experiments performed by the German Nazi doctor Joseph Mengele. It is known, however, that this town was founded by a small number of families and therefore a genetic founder effect may represent an alternatively explanation for the high twinning prevalence in CG. In this study, we tested specific predictions of the "Nazi's experiment" and of the "founder effect" hypotheses. We surveyed a total of 6,262 baptism records from 1959-2008 in CG catholic churches, and identified 91 twin pairs and one triplet. Contrary to the "Nazi's experiment hypothesis", there is no spurt in twinning between the years (1964-1968) when Mengele allegedly was in CG (P = 0.482). Moreover, there is no temporal trend for a declining rate of twinning since the 1960s (P = 0.351), and no difference in twinning among CG districts considering two different periods: 1927-1958 and 1959-2008 (P = 0.638). On the other hand, the "founder effect hypothesis" is supported by an isonymy analysis that shows that women who gave birth to twins have a higher inbreeding coefficient when compared to women who never had twins (0.0148, 0.0081, respectively, P = 0.019). In summary, our results show no evidence for the "Nazi's experiment hypothesis" and strongly suggest that the "founder effect hypothesis" is a much more likely alternative for explaining the high prevalence of twinning in CG. If this hypothesis is correct, then this community represents a valuable population where genetic factors linked to twinning may be identified.

PubMed Disclaimer

Conflict of interest statement

Competing Interests: The authors have declared that no competing interests exist.

Figures

Figure 1
Figure 1. Districts of Cândido Godói with their twin births registration.
Figure 2
Figure 2. Temporal twinning tendencies.
2a: Temporal twinning tendencies in Cândido Godói; 2b: Temporal twinning tendencies in Cândido Godói, excluded Linha Sao Pedro; 2c: Temporal twinning tendencies in Linha Sao Pedro only.
Figure 3
Figure 3. Illustrative pedigree of one family living in Linha São Pedro.
See this image and copyright information in PMC

Similar articles

See all similar articles

Cited by

References

    1. Hall JG. Twinning: mechanisms and genetic implications. Curr Opin Genet Dev. 1996;6:343–347. - PubMed
    1. Lummaa V, Haukioja E, Lemmetyinen R, Pikkola M. Natural selection on human twinning. Nature. 1998;394:533–534. - PubMed
    1. Beemsterboer SN, Homburg R, Gorter NA, Schats R, Hompes PG, et al. The paradox of declining fertility but increasing twinning rates with advancing maternal age. Hum Reprod. 2006;21:1531–1532. - PubMed
    1. Steinman G. Can the chance of having twins be modified by diet? Lancet. 2006;367:1513–1519. - PubMed
    1. Imaizumi Y, Nishida E. The frequency of recurrent multiple maternities using two sets of census data in Japan: 1990 and 1995. Twin Res Hum Genet. 2007;10:638–43. - PubMed

Publication types