U researchers revealed why some dogs8212;such as President Barack Obama’s Portuguese water dog, Bo,8212;have curly hair in a new study published this week.
There were three genes, RSPO2, FGF5 and KRT71, that create seven different coat types for almost 90 percent of all purebred dogs. Dogs with furnishings, mustaches and eyebrows, like schnauzers, get them from the RSPO2 gene. Long-hair or short-hair coats are determined by the FGF5 gene. Curly- and wavy-haired dogs, like Obama’s dog, get their curls from the KRT71 gene.
The researchers studied more than 1,000 dogs belonging to 80 domestic breeds. Purebred dogs have all three of the genes, but the coat of a dog is determined by the presence or absence of an alternative form of one of the genes. For example, Portuguese water dogs have either curly or wavy hair, and the amount of curl depends on which variant of KRT71 gene they have. Bo is described as having curly hair with furnishings, which means he has variants of all three genes.
K. Gordon Lark and Kevin Chase, research specialists for biology, have studied Portuguese water dogs for 13 years and shared data they found for the study. Lark, professor emeritus of biology, also has a Portuguese water dog. Unlike Bo, his dog has wavy hair.
“The degree of curl is controlled by the KRT71 gene,” Lark said.
The KRT71 gene includes a code that develops a structural protein contained in all hair. The protein is what controls the curliness of Portuguese water dogs’ hair and the hair of other curly- or wavy-haired dogs.
The other genes involved in determining a dog’s coat produce proteins that can relate to diseases8212;some that humans share, such as cancer and immune disorders.
Lark said he was surprised to discover that studying why dogs have curly or wavy hair has opened doors for new studies relating to diseases that can affect humans as well. Dogs bred specifically for one trait could become more susceptible to diseases that would shorten their life span. Lark will continue researching and learning how the genes will change in the future.
The National Institute of Health funded the study, which was published online by the Science journal.
