RESUMEN
Regional assignment of eight markers to chromosome 2 of Ateles paniscus chamek (APC) confirmed a syntenic association similar to human (HSA) 12q + 14q + 15q. Three HSA 12q markers (RAP1B, PAH and ALDH2) were allocated to a shortest region of overlap (SRO) in APC 2p and found to be syntenic to other HSA 12q markers (PEPB and TCF1). Five HSA 14q markers (CTLA, PAX9, NSP, FOS and CHGA) were allocated to APC 2q and found to be syntenic to other HSA 14q markers (NP, TGM1, and CALM1) and to four HSA 15q markers (THBS1, B2M, HEXA and MPI) but dissociated from markers close to HSA 14qter (CKB) and HSA 15qter (FES-IDH2). Karyotypic comparisons showed an evident homoeology between APC 2p and HSA 12q while APC 2q was similar to an HSA 14qter::HSA 15qter fusion product. Comparative gene mapping data show that the HSA 14q + HSA 15q syntenic association is an ancestral mammalian gene cluster that has been maintained in several primate taxa. Conversely, in Ateles, it has been further associated with HSA 12q while, in Hominoids and Cebus, it has been independently dissociated into two separate syntenic groups, similar to HSA 14q and HSA 15q.
Asunto(s)
Evolución Biológica , Cebidae/genética , Mapeo Cromosómico/métodos , Cromosomas Humanos Par 2/genética , Animales , Gatos , Cromosomas Humanos Par 12/genética , Marcadores Genéticos , Humanos , Especificidad de la EspecieRESUMEN
Regional assignment of five markers to chromosome 2 of Ateles paniscus chamek (APC) confirmed a syntenic association similar to human (HSA) 12q + 14q + 15q. TCF1 was allocated to a shortest region of overlap (SRO) in APC 2p and found to be syntenic to PEPB, while TGM1, CALM1, THBS1, and B2M were assigned to APC 2q, being syntenic to NP, HEXA, and MPI. Conversely, markers close to HSA 14qter (CKB) and HSA 15qter (FES-IDH2) were relocated to other Ateles syntenic groups. Karyotypic comparisons showed an evident homoeology between APC 2p and HSA 12q, whereas APC 2q was similar to an HSA 14qter::HSA 15qter fusion product.
Asunto(s)
Cebidae/genética , Cromosomas Humanos Par 12 , Cromosomas Humanos Par 14 , Cromosomas Humanos Par 15 , Animales , Evolución Molecular , Reordenamiento Génico , Marcadores Genéticos , Humanos , Células Híbridas , Cariotipificación , Ratones , Ratones Endogámicos BALB C , Especificidad de la EspecieRESUMEN
The Kaingang and Guarani are culturally and linguistically distinct tribes of southern Brazil. Like all Amerindian groups they show limited HLA polymorphism, which probably reflects the small founder populations that colonized America by overland migration from Asia 11,000-40,000 years ago. We find the nucleotide sequences of HLA-B alleles from the Kaingang and Guarani to be distinct from those characterized in caucasian, oriental and other populations. By comparison, the HLA-A and C alleles are familiar. These results and those reported in the accompanying paper on the Waorani of Ecuador reveal that a marked evolution of HLA-B has occurred since humans first entered South America. New alleles have been formed through recombination between pre-existing alleles, not by point mutation, giving rise to distinctive diversification of HLA-B in different South American Indian tribes.