The Frequency of the LCT*-13910C>T Polymorphism Associated with Lactase Persistence Diverges among Euro-Descendant Groups from Brazil.
OBJECTIVE
The aim of this study was to investigate the frequency of the LCT*-13910C>T polymorphism associated with a high expression of lactase in the small intestine during adulthood, and to infer the lactase persistence and adult-type hypolactasia phenotypes among Euro-Brazilians and Mennonites from South Brazil.


METHODS
A sequence-specific PCR method to genotype the LCT*-13910C>T polymorphism in 292 Euro-Brazilians and 151 Mennonites (a group with European ancestry and a long history of endogamy) was developed. Using an exact test of population differentiation, the genotype and allele frequency between these and other Brazilian populations were compared.


RESULTS
The frequency of -13910*T was significantly higher among the Mennonites when compared to the Euro-Brazilian cohort (0.63 vs. 0.33, p < 0.000001). Accordingly, Mennonites had a higher prevalence of the lactase persistence genotype (88.1 vs. 55.5%, p < 0.000001). The distribution of -13910*T differed between Mennonites and all other Brazilian groups (p < 0.0001). The Euro-Brazilians from Curitiba displayed differences when compared to all other Brazilian groups (p < 0.0001), even to Euro-Brazilians from a different geographic region (p = 0.0003), but were similar to those from Porto Alegre (p = 0.2).


CONCLUSIONS
Differences in the -13910*T-associated lactase persistence distribution among Euro-Brazilian groups reflect the ancestry and admixture of each particular group and should be considered for adult-type hypolactasia screening.
Laboratx00F3;rio de Imunopatologia Molecular, Hospital de Clx00ED;nicas, Alto da Glx00F3;ria, Brazil.
Stefanie Epp
SE
Boschmann
Angelica Beate
AB
Boldt
Ilíada Rainha
IR
de Souza
Maria Luiza
ML
Petzl-Erler
Iara Jose
IJ
Messias-Reason
D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D001938:Brazil; D005006:Ethnicity / Q000235:genetics*; D005060:Europe / Q000208:ethnology; D005260:Female; D005787:Gene Frequency; D005838:Genotype; D006801:Humans; D043322:Lactase / Q000235:genetics*; D007787:Lactose Intolerance / Q000235:genetics*; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D020641:Polymorphism, Single Nucleotide; D044465:White People / Q000235:genetics; D055815:Young Adult
D043322:Lactase