Genetic Diversity and Differentiation of Dromedarian Camel of India

Abstract

Estimation of genetic variability and relationship among different livestock breeds is important for management of genetic resources for their sustainable utilization and conservation. This is more important when the livestock species, like camel, have shown a sharp decline in head count during the last decade. In the present study we estimated genetic variability and relationship among four camel breeds of India using 23 microsatellite loci. A total of 252 alleles were observed across all the four populations with mean number of alleles per locus as 8.04, 7.30, 6.39, and 7.43 for Bikaneri, Jaisalmeri, Kutchi, and Mewari breeds, respectively. The mean observed heterozygosity of the four breeds were 0.58, 0.57, 0.56, and 0.60 for Bikaneri, Jaisalmeri, Kutchi, and Mewari breeds, respectively and were lower than expected heterozygosity values. The mean estimates of F statistics were 0.227+/-0.044 (F(IT)), 0.157+/-0.038 (F(IS)), and 0.082+/-0.019 (F(ST)). The values were significantly different from zero for all the three measures and point towards the existence of population structure and moderate differentiation in four camel breeds. The exact test also indicated significant population differentiation (P < 0.001). The analysis of molecular variance revealed 12% of the variation attributed to among populations and 88% within populations. Sixty-nine percent of the individuals could be correctly assigned using "leave one out" procedure. All the individuals of Mewari and 42 out of 44 Jaisalmeri were correctly assigned. The existence of strong population structure in Jaisalmeri and Mewari camel was further substantiated by Nei's standard genetic distance as well as interindividual allele sharing distance. Thus these two breeds owing to selection for specific traits are distinct from other camel breeds.

Assessing genetic diversity of three Tunisian dromedary camel (Camelus dromedarius) sub populations using microsatellite markers

“…Overall, the studied groups exhibited a moderate genetic differentiation of 5.2%, while the remaining 94.8% of the genetic variability was attributed to the differentiation within sub-populations (between individuals). This value was comparable to the genetic differentiation level previously reported (8.3%) for Tunisian camel population (Ould Ahmed et al, 2010), for Indian camel population (8.2%) (Vijh et al, 2007) and for Majorero camel in Canary Islands (3.1%) (Shulz et al, 2005). The within sub-population inbreeding estimate, per group across loci, were -0.369 (AT), -0.258 (AB) and -0.265 (ME).…”

Genetic and demographic bottleneck analysis of Indian camel breeds by microsatellite markers

“…It is evident from the above observation that Kachchhi and Mewari breeds have relatively less genetic variation as compared to the Bikaneri and Jaisalmeri, it is further substantiated by the fact that the Mewari is the least numerous and Kachchhi is the second least numerous breed of camel in India (Mehta et al 2011). The number of alleles and allele size range observed in the present investigation were broadly in agreement with the literature (Obreque et al 1998;Sasse et al 2000;Jianlin et al 2000;Vijh et al 2007;Spencer and Woolnough 2010;Banerjee et al 2012). Slight differences in the number of alleles and hence frequencies were expected due to the existence of actual genetic differences among the stocks used by different researchers.…”

Assessment of genetic diversity and differentiation of two major camel ecotypes (&lt;i&gt;Camelus dromedarius&lt;/i&gt;) in Sudan using microsatellite markers

“…The Kenyan and South African dromedaries have not been subjected to intensive selection (Mburu et al, 2003;Nolte et al, 2005); therefore this may be a possible reason for having a comparable MNA to ours. Analyses of 23 loci within 4 Indian dromedaries (Vijh et al, 2007) and 18 loci within 10 Chinese and Mongolian Bactrians (Xiaohong et al, 2012) yielded MNA values that were reasonably higher than ours.…”

“…Polymorphic information content and H e estimates within current ecotypes were higher compared with Kenyan and United Arab Emirates (Mburu et al, 2003), Indian (Vijh et al, 2007), Tunisian (Ould Ahmed et al, 2010), Chinese, Mongolian (Xiaohong et al, 2012) and Saudi Arabian camels (Mahmoud et al, 2012(Mahmoud et al, , 2013. Nonetheless, study ecotypes showed lower H e values than Egyptian camel breeds (Karima et al, 2011).…”

“…Mburu et al (2003) identified two separate genetic entities present in Kenyan dromedaries using 14 microsatellites. Vijh et al (2007) indicated, based on 23 microsatellite markers, that there were two distinct genetic clusters in the Indian dromedaries. Ould investigated eight microsatellites, reporting high genetic variability within three Tunisian dromedaries.…”