The Eld’s deer Rucervus eldii once distributed throughout Southeast Asia extending from northeast India to Indochina and southern China is now confined to small fragmented areas. Four subspecies were identified; R. e. eldii in Manipur, India, R. e. thamin in central plains of Myanmar and western Thailand R. e. siamensis in Lao PDR and in the northern and eastern Cambodia and a fourth subspecies R. e. hainanus in Hainan’s Island China. The review revealed few molecular investigations have been conducted on the genetics of Eld’s deer based on karyotype analysis, mtDNA and microsatellites. Studies based on mtDNA control region have shown that population of R. e. eldii showed closest relationship with R. e. thamin than to R. e. siamensis.  Microsatellites studies are limited to R. e. hainanus; the genetic variability was low suggesting that founder effects and genetic drift have affected the population. There still remain many knowledge gaps in the systematic and genetic status of this species. The population of Eld’s deer suggested ≈2165 individuals by 2003 spreading over nine reserves. Population sizes of most subspecies of Eld’s deer are small and threatened due to effects of inbreeding depression, loss of genetic variability and drift. Environmental fluctuations due to variation in predation, competition, disease, poaching, habitat deterioration and natural catastrophes are some of the other reasons affecting the population. In future, more research is required to determine the genetic population structure on the basis of markers, variable enough to detect differences between the subspecies. An extensive study is required to assess the relatedness and kinships among captive and wild population so that changes in genetic variability could be identified and appropriate conservation measures are taken. Genetic monitoring of both the source and reintroduced populations should be done prior to reintroduction in order to assess effectiveness of conservation program.

Keywords:  Conservation genetics, Distribution, Eld’s deer, Population status, Systematics