Exploring the Full Genome Sequence of Dromedary Camels from the Arabian Penninsula

The dromedary camels (Camelus dromedarius) are even-toed ungulates populating the Northern and Eastern part of Africa, Arabian Peninsula and the Southwestern part of Asia. They are single hump species highly adapted to the harsh desert environment (high temperature and scarcity of water). In addition of their initial use as packing animals they are currently considered as a source of milk, meat as well as used in racing and beauty contests. Here, we report the analysis of the full genome sequence of six dromedaries from the Arabian Peninsula (4 milk-producing and 2 racing) to evaluate their genetic diversity and relationships, and to identify genetically differentiated regions (F_ST) between the two types. The sequence reads were mapped on ~ 97% of the reference dromedary genome (GenBank accession code: JDVD00000000) with an average depth of coverage of 12X. The average number of single nucleotide polymorphism (SNP) and insertion/deletion (Indel) in racing camels, 2.33 million and 313 thousands respectively, are higher than in milk-producing camels, 2.3 million and 309 thousands respectively. Among the identified SNPs, 50,158 and 71,482 are specific to milk-producing and racing camels, respectively. Racing camels also show slightly higher degree of homozygosity than milk-producing camels. Principle component analysis clearly differentiated racing and milk-producing camels. Moreover, 65 candidate regions are identified that show genetic differentiation between the two types. Analysis of more samples from each type may further validate the candidate regions and variants of differentiation identified here.