Genetic diversity, structure, and admixture in Mayans from Guatemala and Mexico based on 15 short tandem repeats

To analyze the genetic origin, relationships, structure, and admixture in Mayan Native American groups from Guatemala and Mexico based on 15 autosomal short tandem repeats (STRs) loci commonly used in human identification (HID).

We genotyped 513 unrelated Mayan samples from Guatemala based on 15 STR loci (AmpFlSTR® Identifiler kit). Moreover, we included 4408 genotypes previously reported, as following: Mayas from Guatemala and Mexico (n = 1666) and from Latin American, European, and African (n = 2742) populations. Forensic parameters, genetic distances, admixture, and population structure were assessed.

Forensic parameters of the 15 STRs in different Mayan groups from Guatemala were reported. Low (Fst = 0.78%; p = 0.000) and non-significant differentiation (Fst = 1.8%; p = 0.108) were observed in Mayas from Guatemala and Mexico, respectively. The relative homogeneity observed among Mayan groups supported theories of extensive pre-Columbian gene flow and trade throughout the Mayan Empire. The distribution of the three Native American ancestries among these Mayan groups did not support the presumable Guatemalan origin of Tojolabal and Lacandon people (South, Mexico). The nonsignificant differentiation between Ladinos and Mayas suggests a relative panmixia in Guatemala. Mestizos from southeastern Mexico and Guatemala constitute a core of Native American ancestry in Latin America related to the Mayan Empire in Central America.

The higher European admixture and homogeneity in Mexican Mayas of the Yucatan Peninsula suggest more intensive post-Columbian gene flow in this region than in Guatemalan Mayas.