Humans & Dogs Sharing DNA?

By Tamara Sevigny

Recently scientists have decoded the complete genome of the domestic dog providing a biological roadmap for unraveling human diseases and even helping to explain the mysterious bond between man and dog.
It took two years and dozens of researches to analyze the 19,300 genes belonging to a Boxer named Tasha. They found a huge similarity between dog and human DNA, according to a study published in the journal Nature.
"Humans and dogs have essentially the same genes," said the lead author Kerstin Lindblad-Toh, co-director of the genome sequencing and analysis program at the Broad Institute of MIT and Harvard University. "Every gene has a gene with the same function in the other genome."
The closeness in genes explains the several shared diseases of dogs and humans including cancer, blindness, heart disease, diabetes and epilepsy. In fact, of the 10 most common diseases in dogs, 8 are important to humans.
The study offers the possibility that characteristic dog breeds, those breed for behavioral traits, may help illuminate the elusive genetic instructions that account for countless variability of human personalities.
Tasha, the pure-bred Boxer chosen for the study was picked out of a possible 120 dogs screened by the National Human Genome Research Institute in Bethesda, MD. She was chosen based on the fact that she had the least amount of variation among the candidates. Her photo now hangs proudly at the Mammalian Wall of Fame at the Broad Institute in Cambridge, MA, where the sequencing work was completed.
The dog genome consists of 2.5 billion chemical letters compared to the 3 billion for humans. In investigating Tasha’s genome and comparing it to genetic data of 10 other breeds they cataloged more then 2.5 million genetic differences that can occur in dogs, which creates the ranges in size, shape, color, temperaments and even tendency for disease in various dog breeds.
Dogs are unique among mammals because of the selective breeding that began a few hundred years ago, creating the approximate 400 breeds that exist today.