Evolution within the Diving Bajau People

It has been found that the Bajau people, who reside in scattered communities in Indonesia, Malaysia, and the Philippines, may have evolved traits that make them better divers. The Bajau people dive for their livelihood, and have been doing so for centuries. Many have noticed that the Bajau people are more gifted than others in diving, as the Bajau people were observed to be able to dive more than 200 feet with their only equipment being wooden goggles. Dr. Melissa Ilardo, a geneticist, set out to study the people to see if they had, indeed, evolved traits that could aid them in diving. She visited the villages of the Bajau people and measured the size of their spleens, which have been found to play a key role in how deep an organism is able to dive. The larger the spleen, the deeper an organism is able to dive. Dr. Ilardo measured the spleens of nearby farmers that were not Bajau, and she compared the sizes to the Bajau people. She found that the spleens of the Bajau people were 50% larger than the spleens of the neighboring farmers. After conducting a DNA test, it was also found that the Bajau people shared a number of variant genes, which further suggested that natural selection had taken place within the population. A variant of a gene, PDE10A, was found within the DNA of the Bajau people; this variant influences the size of spleens. The more copies one has of the PDE10A variant, the larger that person’s spleen will be. The studies performed are not conclusive, however, and more research needs to be performed on the matter.

I found this article to be really interesting. The evolution between groups of people intrigues me, as it sounds amazing that a certain group of people can evolve to have a set of traits from other humans that help them survive better under certain conditions. It seems that, compared to humans like me, who live in a more neutral environment, it is as if the Bajau people have a biological advantage. The fact that the Bajau people are able to dive to depths of over 200ft, and at that rate, are able to hold their breath for long enough to dive that far down, shows how far the limits are that the human body can be pushed to. I also found it very heartwarming that the researcher who was performing the studies had such love for her research, and was so passionate as to travel all the way to the islands that the Bajau people live on in order to perform tests. Reading about how interesting the evolution of the Bajau people was, and how much Dr. Ilado loved her job, it made me imagine how fun it must be to be a geneticist researching the biological evolution of groups of humans.

New Genes in Sardinia

Recently, Sardinia became apart of the genomic world map for it's newest discoveries of genes and mutations. The SardiNIA project, led by Francesco Cucca, Goncçalo Abecasis, David Schlessinger and John Novembre, found over 17 million new genes after studying the genomes of 2,120 Sardinians. Twenty two percent of these genes were not found anywhere else, and 76,000 of the genes were rare in these populations. The SardiNIA project took much time to analyze these genes for future application.

Map of Sardinia

Some of the specific data found include variants of circulating lipid levels and five inflamatory biomarker, which correspond to two new loci each, They also found the HBB mutation, which is associated with reduced cholesterol levels, the APOA5 missennce variant, which reduces the body's triglyceride levels, a nonsense mutation in GHR, a gene involved with with Laron syndrome, and a mutation involved with KCNQ1. These mutations did not even exist in the 1,000 genomes project. The SardiNIA project even studied the effect of genetic drift on small islands, and concluded that organisms reduce in size once they separate to other islands. In due time, the SardiNIA project will find more data, and promote further research on this new island.




Original Article

Second Article