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Full Length Research Paper
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Six SNPs and
a TTG indel in sheep desmoglein 4 gene are in complete
linkage disequilibrium
Ge Zhang1,
Yue-hui Ma1, Yuan-yue Zhang2, Wei-jun
Guan1, Qian-jun Zhao1,
Hui-jing Zhao1 and Jian-lin Han1,3,4*
1Key Laboratory of Farm
Animal Genetic Resources and Utilization of Ministry of
Agriculture, Institute of Animal Science, Chinese Academy of
Agricultural Sciences (CAAS), Beijing 100193, China.
2Department of Animal
Science and Technology, Hunan Agricultural University,
Changsha 410128, China.
3International
Livestock Research Institute (ILRI), P.O. Box
30709, Nairobi 00100, Kenya.
4CAAS-ILRI
Joint Laboratory on Livestock and Forage Genetic Resources,
Institute of Animal Science, Chinese Academy of Agricultural
Sciences (CAAS), Beijing 100193, China.
*Corresponding
author. E-mail:
h.jianlin@cgiar.org.
or
hanjl@iascaas.net.cn.
Tel/Fax: +(86-10) 62829175.
Accepted 13 June, 2011 |
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Abstract |
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Desmoglein 4 (DSG4) plays an important role in the regulation of
growth and differentiation of hair follicles in mammals. In this
study, a 755 bp long segment of DSG4 was screened in 544
sheep sampled from nine Chinese indigenous breeds and two
Western breeds using PCR-SSCP assay with three different pairs
of primers. Two of the three fragments showed polymorphisms with
genotypes defined as AA, AB, BB and BC, and DD, DE, and EE,
respectively. Interestingly, polymorphisms in these two
fragments were in strong linkage disequilibrium. Only three
haplotypes were found, of which haplotype AD determined by
alleles A and D was the major one in all breeds, while haplotype
BE was only found in Chinese breeds that possess divergent
frequencies ranging from 0.02 to 0.43; haplotype CD was very
rare and present in only one Chinese sheep. Sequences of the
three haplotypes showed seven single nucleotide polymorphisms (SNPs)
and a TTG insertion/deletion (indel), leading to five amino acid
substitutions and a glycine indel. Our study provides valuable
genetic markers in evaluating the impact of the DSG4
gene on wool traits in sheep.
Key words:
Sheep, DSG4 gene, single-strand conformational
polymorphism (SSCP), variation, linkage disequilibrium. |
