Population genetic structure of the camel, Camelus dromedarius based on microsatellite loci: Knock-on effect for conservation

Camelus dromedarius is a widely distributed animal of North-Western region of India. Microsatellite markers were used to infer the genetic structure of C. dromedarius and to identify management units and support conservation planning. The genetic structure was accessed by analyzing twenty five microsatellite loci in 689 individuals of C. dromedarius belonging to six populations from different geographical area. A total of 390 alleles were estimated in the genotyped sample. The mean effective number of alleles were calculated 3.108 +/- 0.349, 2.685 +/- 0.253, 2.895 +/- 0.281, 1.972 +/- 0.227, 2.571 +/- 0.266 and 3.326 +/- 0.311 for Malvi, Mewari, Mewati, Bikaneri, Jaisameri and Kutchhi respectively. The average observed heterozygosity in the present study (0.469 +/- 0.026) was significantly lower than expected heterozygosity (0.538 +/- 0.018), which reflect that the camel population of India has a significant population structure. Estimated F-IS (0.189) value indicates a certain level of heterozygote deficiency. The demographic parameters were tested using various mutation models. A significant heterozygote excess on the basis of different models, as revealed from Sign and Wilcoxon rank test suggested that C. dromedarius population is not in mutation-drift equilibrium. Mode-shift test showed a normal 'L' shaped distribution for allelic class and proportion of alleles, thus indicating the absence of bottleneck events in the recent history of this breed. The present work is a contribution to the knowledge of population structure and to the assessment of genetic diversity that may be helpful to camel breeders in designing and managing breeding or conservation strategies for the dromedarian camel.