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Journal of Zhejiang University SCIENCE B 2008 Vol.9 No.12 P.931~937


Influence of outliers on QTL mapping for complex traits

Author(s):  Yousaf HAYAT, Jian YANG, Hai-ming XU, Jun ZHU

Affiliation(s):  Institute of Bioinformatics, College of Agriculture and Biotechnology, Zhejiang University, Hangzhou 310029, China; more

Corresponding email(s):   jzhu@zju.edu.cn

Key Words:  QTL mapping, Outliers and influential observations, Complex trait

Yousaf HAYAT, Jian YANG, Hai-ming XU, Jun ZHU. Influence of outliers on QTL mapping for complex traits[J]. Journal of Zhejiang University Science B, 2008, 9(12): 931~937.

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author="Yousaf HAYAT, Jian YANG, Hai-ming XU, Jun ZHU",
journal="Journal of Zhejiang University Science B",
publisher="Zhejiang University Press & Springer",

%0 Journal Article
%T Influence of outliers on QTL mapping for complex traits
%A Yousaf HAYAT
%A Jian YANG
%A Hai-ming XU
%A Jun ZHU
%J Journal of Zhejiang University SCIENCE B
%V 9
%N 12
%P 931~937
%@ 1673-1581
%D 2008
%I Zhejiang University Press & Springer
%DOI 10.1631/jzus.B0820045

T1 - Influence of outliers on QTL mapping for complex traits
A1 - Yousaf HAYAT
A1 - Jian YANG
A1 - Hai-ming XU
A1 - Jun ZHU
J0 - Journal of Zhejiang University Science B
VL - 9
IS - 12
SP - 931
EP - 937
%@ 1673-1581
Y1 - 2008
PB - Zhejiang University Press & Springer
ER -
DOI - 10.1631/jzus.B0820045

A method was proposed for the detection of outliers and influential observations in the framework of a mixed linear model, prior to the quantitative trait locus (QTL) mapping analysis. We investigated the impact of outliers on QTL mapping for complex traits in a mouse BXD population, and observed that the dropping of outliers could provide the evidence of additional QTL and epistatic loci affecting the 1stBrain-OB and the 2ndBrain-OB in a cross of the abovementioned population. The results could also reveal a remarkable increase in estimating heritabilities of QTL in the absence of outliers. In addition, simulations were conducted to investigate the detection powers and false discovery rates (FDRs) of QTLs in the presence and absence of outliers. The results suggested that the presence of a small proportion of outliers could increase the FDR and hence decrease the detection power of QTLs. A drastic increase could be obtained in the estimates of standard errors for position, additive and additive× environment interaction effects of QTLs in the presence of outliers.

Darkslateblue:Affiliate; Royal Blue:Author; Turquoise:Article


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