Genetics, Playing a Key Role in Obesity

A recent study conducted at Brigham Young University in Utah, USA has found new evidence to suggest that obesity may be linked to genetics. The study involved examining evolutionary selection on Pima Indians, indigenous to the Sonora Desert of Arizona and New Mexico. It is known that there is a high rate of obesity among the modern Pima Indians and this is thought to be due to their fast metabolism which was advantageous during times when food was scarce. However problems arise when food is in abundance, leading to high rates of obesity in modern Pima communities. Two hundred obese Pima individuals were included in the study, with their metabolic rates being measured. With the researchers focusing on changes in their mitochondrial DNA or SNP’s (single nucleotide polymorphisms) they found that two of the three known SNP’s influence metabolic efficiency. The researchers then used software to analyze and track these variations across a number of different mammals leading to their proposal that variations in these SNP’s affect the mitochondrial respiration chain and consequently causes change in metabolic rate. Although the study focused primarily on the Pima Indians, similar variations in SNP’s can be found in other populations. Where a high metabolic rate was an advantage in the past, it can now be seen as detrimental as there is an abundance of food leading to high and increasing rates of obesity in populations all around the world. This study found evidence to suggest that genetics play a key role in obesity. http://www.sciencedaily.com/releases/2007/10/071016074958.htm