Dr. Shen, Chen-Yang

Distinguished Research Fellow
  • 02-27899036 (Lab) (Room No: N143)
  • 02-27823047 (Fax)

Specialty:
  • Molecular Epidemiology
  • Cancer Genetics
  • Personalized Medicine

Education and Positions:
  • Ph.D. Univ. of North Carolina at Chapel Hill


Highlight Detail
...

Detecting Genetic Ancestry and Adaptation in the Taiwanese Han People

Dr. Shen, Chen-Yang
Molecular Biology and Evolution, Dec 18, 2020

Abstract

The Taiwanese people are composed of diverse indigenous populations and the Taiwanese Han. About 95% of the Taiwanese identify themselves as Taiwanese Han, but this may not be a homogeneous population because they migrated to the island from various regions of continental East Asia over a period of 400 years. Little is known about the underlying patterns of genetic ancestry, population admixture, and evolutionary adaptation in the Taiwanese Han people. Here, we analyzed the whole-genome single-nucleotide polymorphism genotyping data from 14,401 individuals of Taiwanese Han collected by the Taiwan Biobank and the whole-genome sequencing data for a subset of 772 people. We detected four major genetic ancestries with distinct geographic distributions (i.e., Northern, Southeastern, Japonic, and Island Southeast Asian ancestries) and signatures of population mixture contributing to the genomes of Taiwanese Han. We further scanned for signatures of positive natural selection that caused unusually long-range haplotypes and elevations of hitchhiked variants. As a result, we identified 16 candidate loci in which selection signals can be unambiguously localized at five single genes: CTNNA2LRP1BCSNK1G3ASTN2, and NEO1. Statistical associations were examined in 16 metabolic-related traits to further elucidate the functional effects of each candidate gene. All five genes appear to have pleiotropic connections to various types of disease susceptibility and significant associations with at least one metabolic-related trait. Together, our results provide critical insights for understanding the evolutionary history and adaption of the Taiwanese Han population.

 

台灣漢族遺傳組成與遺傳適應的全面分析

台灣人由台灣漢族與不同的原住民所组成。大约95%的台灣人是台灣漢族,但是漢族本身雖然稱為同文同種,但是經過兩三千年的遺傳演化遷徙與其他中國大陸各民族的通婚,在微觀遺傳來看,也並非完全的同質性人口,而自四百年前起,從東亞大陸的各個地區遷移到台灣島。對於台灣漢族人的遗傳血统,種群混合與演化適應的遺傳模式在目前還沒有完全廣泛性的研究。在本研究中,我們分析了Taiwan Biobank的參與者,包含有台灣漢族族人共14401位。這些參予者已經完成全基因體單核甘酸變異(single-nucleotide polymorphisms, SNPs)的基因分型分析(Genotyping),以及其中772位有全基因體定序(whole-genome sequencing) 資料。本研究檢测到四種具有不同地理分布的主要遗傳來原(包括北方漢人,東南亞漢人,具有某部分琉球日本語系的台灣漢人和與南島語系民族的遺傳血統),以及構成台灣漢族基因體的族群混合的特殊遺傳學特徵。本研究進一步篩檢正向自然選擇(Positive natural selection)的遺傳標幟,這些遺傳標幟導致了異常長度的單倍體(haplotype),但這些較長的單被體也免不了帶著可能具有負向自然選擇(Negative natural selection)的變異。研究結果顯示,我們確認了16個候選基因位位置,這些位置在五個基因上:CTNNA2,LRP1B,CSNK1G3,ASTN2和NEO1。在與16種代谢疾病相關性狀的相關分析中,我們發現所有這五個基因與多種代谢疾病相關性狀的疾病易感性具有多重的關聯,並且與至少一種代谢疾病相關性狀呈現統計顯著的相關。我們的结果首次為了解台灣漢族人口的演化歷史和演化適應提供關鍵的訊息。