Evaluating the gene flow from East to West among various populations of Rajasthan, India

Background: The genetic landscape of South Asia is distinctive, where there is a preponderance of social-cultural and genetic variability. Rajasthan is a state located in the north-western part of India and it has been cited as a major route of human migration since ancient times. The present study was conducted to find out the genetic affinity of Rajasthani population with the population living in its east and the west. In particular, we compared them with the population of Pakistan which shares the common geographical boundary with the Rajasthan while also having a look at their inter and intra population affinities with the population belonging to other Indian states. We investigated the genetic structure and population parameters of Rajasthani populations obtained for twenty polymorphic autosomal STR loci from 669 unrelated individuals belonging to its three population groups including Mina, Gujjar and the mixed population of Rajasthan. Results: The studied populations showed a wide range of genetic diversity and besides the genetic structure of the studied populations, it was found that the average heterozygosity value was highest among the populations of Rajasthan, possibly, because of gene flow from different directions. Conclusion: Various statistical analyses suggested that the Rajasthani populations had a higher affinity with the North Indian populations rather than with the Pakistani population.

in increasing the level of endogamy along with the social factors. Rajasthan is considered as the major land route of human migration [4]. Prehistoric archeological evidence of Indus valley civilization is also found in this state which reflects the population diversity found in this particular region. On the western side, it shares the geographical boundaries with Pakistan and it comprises the "Thar Desert" which is also known as "Rajasthan or great Indian desert". In the north, east and south, it shares the geographical boundaries with various Indian states viz. Punjab, Haryana, Uttar Pradesh, Madhya Pradesh and Gujarat [5]. The Rajasthani people consider themselves as native inhabitants of Rajasthan state and speaks various dialects of Indo-Aryan linguistic group [6]. As per Census 2011, the population of Rajasthan state was 68.6 million, which was 5.66% of the total population of the country. 57.13% of the total population of Rajasthan lives in the rural areas [7].
Mina community is the dominating tribal population mostly found in western and central Indian states of Rajasthan and Madhya Pradesh. The word Mina is derived from Sanskrit word 'Meen' which means fish, and Minas claim to be mythological descendants of Matsya avatar of lord Vishnu[8] [9]. It is believed that Minas are mixed and impure caste and sometimes it has been supposed that they originated from a branch of Rajputs [10]. The Minas are believed to be a pre-Aryan tribe of Rajputana province in the beginning. The Mina tribe is divided into two branches, "Jamindars", who adopted agriculture as a profession and "Chowkidars" who worked as watchmen [11] [12].
Gujjar also known as Gurjar, Goojr and Gojar is a middle class community which is mainly spread in north-west India. In India, Gujjars arrived between 5th and 6th century (470-520 AD) [13]. They played diverse historical roles in society. For example, while on one hand, they were founders of many kingdoms, on the other hand many of them were nomads. Now a day, these people are engaged in agriculture along with dairy and livestock farming and this community has its own socio-cultural identity. [5] [13].

Results:
In this study, we investigated the genetic affinity of studied populations with the reported population

Conclusion:
In conclusion, we found that studied populations i.e. Mina, Gujjar and the mixed population of Rajasthan showed genetic affinity with populations of North and Central Indian populations rather than Pakistan. In spite of their geographical location, they are more homogeneous when intra-population comparison is done. The data obtained from the studied populations of Rajasthan enriches the database and can be used for human identification and anthropological studies.

Participants and Sample collection
This study was conducted in compliance with ethical standards and was approved by the Institutional Ethical Committee of the Jaipur National University, Jaipur, Rajasthan, India, vide letter no.

DNA Extraction and Genotyping
The samples were directly amplified without DNA extraction using PowerPlex ® 21 multiplex system (Promega, CA, USA) as per recommendations of the manufacturer's except that the 10 µl reaction volume was used. The direct amplification protocol was initially standardized and the profiles generated by the direct method were compared with the DNA profiles obtained from the extracted DNA using standard organic extraction method Phenol Chloroform Isoamyl Alcohol (PCIA) as described earlier [17] [18]. The Amplified DNA fragments were analyzed by using ABI 3500XL Genetic Analyzer using 36 cm capillary and POP TM -4 (Thermo Fisher Scientific, USA-Thermo). Allelic ladder provided along with kit was used to obtain the DNA profiles. Data was analyzed using GeneMapper TM ID-X Software Version 1.5 (Thermo). The peak height threshold was 50 and 200 Relative Fluorescence Unit (RFU) for the heterozygous and homozygous allele respectively.

Quality Control:
Quality control standards for this study were followed. The authors have passed the proficiency test of

Availability of data and materials:
The datasets used and/or analyzed during the current study are available from the corresponding author on reasonable request.

Competing Interests: The authors declare no competing interest
Funding: The author(s) received no specific funding for this work.  Table 1 Due to technical limitations, table 1 only available as a download in the supplemental files section. Figure 1 The

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