Life Science and Medical News from Around the Globe
Corn Snake Genome Sequenced, Genetic Cause of Corn Snake Albinism Identified; Gene Controlling Acidity in Snake Melanosomes Is Mutated by Insertion of LTR-Retrotransposon
Among the 5 000 existing species of mammals, more than 100 have had their genome sequenced, whereas the genomes of only 9 species of reptiles (among 10,000 species) are available to the scientific community. This is the reason why a team at the University of Geneva (UNIGE), Switzerland, has produced a large database including, among other genomes, the newly-sequenced genome of the corn snake, a species increasingly used to understand the evolution of reptiles. Within the same laboratory, the researchers have discovered the exact mutation that causes albinism in that species, a result published online on November 24, 2015 in an open-access article in Scientific Reports. The article is titled “Amelanism in the Corn Snake Is Associated with the Insertion of an LTR-Retrotransposon in the OCA2 Gene.” Genomics allows better investigation of the evolution of the living world. Indeed, describing the function of each gene should allow an understanding how snakes lost their limbs or how various snake skin colorations have evolved. Unfortunately, reptiles are poorly represented in genomic databases. This is why Dr. Athanasia Tzika, a researcher in the Department of Genetics and Evolution of the UNIGE Faculty of Sciences, has built a database including sequenced genomes from the major evolutionary lineages of reptiles: the Reptilian Transcriptomes Database 2.0. “Our aim was to produce, ourselves, a substantial portion of the missing data by sequencing all genes from several reptilian species. To reach this goal, we used tissues, such as the brain and the kidney, expressing the largest number of genes,” says Dr. Tzika. Multiple other teams also generated sequencing data, but each team used different methods for data analysis, making it difficult to rigorously study the evolution of reptilian genomes. Consequently, a key part of Dr.