title: Genetic origins in a South American clefting population.
abstract: It has been proposed that susceptibility to clefting in South America is related to Amerindian ancestry, where clefting is present at a higher frequency than in the other admixed populations (Caucasian and African) that make up the diverse racial mix of current South Americans. To clarify the genetic origins and establish a method for genetic mapping, mitochondrial DNA variation and Y-chromosome markers were studied in a South American population affected with clefting. Two-hundred and seventeen subjects and matched controls were selected through the Latin-American Collaborative Study of Congenital Malformations (ECLAMC). The case group showed a higher frequency of Native American haplogroups and a lower frequency of African haplogroups (p < 0.00001). In addition, the case group showed a much higher frequency of the specific native American haplogroup D than the control group (p < 0.00001). For the Y-chromosome markers, the case group showed a lower frequency of the African-specific marker, YAP (p = 0.002), and a higher frequency of the Native American-specific marker, DYS199 (p < 0.00001). Even though differences were found in the frequencies of the markers studied, the contribution of each founder population was similar for both groups. Results suggest a strong Native American maternal contribution and a strong Caucasian (Spanish and Portuguese) paternal contribution to the population studied. The implications of this finding include the possibility of using admixture mapping approaches to this population.
authors.affiliation: Department of Pediatrics, University of Iowa, Iowa City 52242-1083, USA.
authors.forename: A R
authors.initials: AR
authors.lastname: Vieira
authors.forename: J C
authors.initials: JC
authors.lastname: Karras
authors.forename: I M
authors.initials: IM
authors.lastname: Orioli
authors.forename: E E
authors.initials: EE
authors.lastname: Castilla
authors.forename: J C
authors.initials: JC
authors.lastname: Murray
mesh_terms: D041322:Chromosomes, Human, Y; D002971:Cleft Lip / Q000208:ethnology / Q000235:genetics*; D002972:Cleft Palate / Q000208:ethnology / Q000235:genetics*; D004272:DNA, Mitochondrial; D004641:Emigration and Immigration; D018703:Founder Effect; D005819:Genetic Markers; D014644:Genetic Variation; D006801:Humans; D040582:Inheritance Patterns; D013020:South America / Q000208:ethnology
chemical_list: D004272:DNA, Mitochondrial; D005819:Genetic Markers