Cobalamin (Vitamin B_(12)) Deficiency in the Chinese Shar Pei – Evaluation of a Potential Hereditary Etiology

Abstract

In recent history, no other dog breed has grown in popularity and/or population size in such a short period of time as is the case for the Chinese Shar Pei in North America. After being introduced to North America in the 1970s, the breed suffered from rushed breeding carried out by inexperienced breeders. This resulted not only in a dramatically different look for the Chinese Shar Pei breed, but also in a large number of health problems. A report from 1991 revealed that Chinese Shar Pei have a predisposition for cobalamin deficiency. In this context, a comparison of serum cobalamin concentrations between dogs of different breeds would help to better understand this condition in the Chinese Shar Pei. Cobalamin-deficient Chinese Shar Peis show several clinical signs, which can be characterized by inflammatory markers, markers for chronic intestinal disease, and immunological markers. Other serum markers of cobalamin-related cellular biochemistry include homocysteine and methylmalonic acid, which are a reflection of intracellular cobalamin availability and thus might provide insights in the intracellular cobalamin metabolism in Chinese Shar Peis with cobalamin deficiency. The Chinese Shar Pei phenotype changed over the last few decades and a survey would identify which of the two types (i.e., traditional type vs. meatmouth type) is more commonly affected with cobalamin deficiency. Genetically speaking, genome-wide scans can be used to identify potential regions on the canine chromosome that are linked to cobalamin deficiency in Chinese Shar Peis. Further sequencing may identify the actual mutation responsible for the condition in this breed.