title: Lactase persistence may have an independent origin in Tibetan populations from Tibet, China.
abstract: Milk consumption is prevalent in daily diets of Tibetans. To digest the milk sugar lactose, lactase persistence (LP) should be required. However, little is known about the genetic basis of LP in Tibetans. We screened 495 Tibetan individuals for five previously reported single-nucleotide polymorphisms (SNPs): -13907C/G (rs41525747), -13910C/T (rs4988235), -13915T/G (rs41380347), -14010G/C and -22018G/A (rs182549), which are associated with the LP in populations from a vast region surrounding Tibet. The five SNPs were nearly absent in Tibetan populations, suggesting LP likely to have an independent origin in Tibetans rather than to be introduced via gene flow from neighboring populations. We identified three novel SNPs (-13838G/A, -13906T/A and -13908C/T) in Tibetans. In particular, -13838G/A might be functional as it is located in the binding motif for HNF4α that acts as a transcription factor for intestinal gene expression. To investigate the potential association of this variant with LP, further detailed studies are required in the future.
authors.affiliation: State Key Laboratory of Genetic Resources and Evolution, Kunming Institute of Zoology, Chinese Academy of Sciences, Kunming, China.
authors.forename: Min-Sheng
authors.initials: MS
authors.lastname: Peng
authors.forename: Jun-Dong
authors.initials: JD
authors.lastname: He
authors.forename: Chun-Ling
authors.initials: CL
authors.lastname: Zhu
authors.forename: Shi-Fang
authors.initials: SF
authors.lastname: Wu
authors.forename: Jie-Qiong
authors.initials: JQ
authors.lastname: Jin
authors.forename: Ya-Ping
authors.initials: YP
authors.lastname: Zhang
mesh_terms: D000483:Alleles; D044466:Asian People / Q000235:genetics*; D001665:Binding Sites; D004742:Enhancer Elements, Genetic; D005787:Gene Frequency; D056726:Genetic Association Studies; D006801:Humans; D043322:Lactase / Q000235:genetics* / Q000378:metabolism*; D059372:Nucleotide Motifs; D020641:Polymorphism, Single Nucleotide; D018609:Tibet
chemical_list: D043322:Lactase