London: Scientists have explained how the Shar-pei breed of dogs gets its famous wrinkled appearance. According to BBC, scientists who have analyzed the genetics of 10 pedigree dog breeds believe they now have the answer.
Scientists have long been curious to understand what changes in dog genes brought about by breeding resulted in the wide spectrum of body types, coat colors, fur, and temperaments present in the more than 400 genetically distinct dog breeds today.
A new study has laid down the first pieces of this puzzle by sequencing large sections of genes from nearly 300 dogs belonging to 10 different breeds. Among the study`s findings, detailed in journal Proceedings of the National Academy of Sciences, is the identification of the gene likely responsible for the exaggerated wrinkles in the skin of Shar-Peis.
The pedigree dog has become a fascination - and a remarkably useful research tool - for geneticists.
The domestication of the grey wolf more than 10,000 years ago, and the selective breeding that followed, has resulted in more than 400 breeds - each with a distinctive physique, coat colour and temperament.
These discrete populations give scientists the opportunity to compare and contrast the genetics of the different groups, making it easier to find the causes of specific traits.
"Man`s best friend" is helping scientists locate the faulty genes that cause disease in both dogs and humans, as well giving a useful insight into how evolution works at a molecular level.
Dr Akey and colleagues studied 32 wrinkled and 18 smooth-coated Shar-peis and compared a specific stretch of their DNA with that of other breeds.
The team found four small, but significant, differences in the genetics of the two skin types of the Shar-pei versus the other breeds. These single nucleotide polymorphisms (SNPs), as they are called, were located in the HAS2 gene.
As well as giving insights into the Shar-pei, the research has also identified a raft of other locations in the dog genome that can now be investigated further to understand better why pedigree animals look the way they do.
"The thing that excites me most about our study is that in the last five years, five genes have been identified that contribute to this vast diversity in dog breeds," said Dr Akey.
"So our study found all five of those genes and then we found 150 new targets to explore. It`s a powerful approach to look at the genetic legacy of selective breeding."
Dr Akey and colleagues report their findings in the Proceedings of the National Academy of Sciences (PNAS).