No Mr.Gaunder, religion is not acquired by birth. There is, and cannot be, any biological proof for that. It does not come thru your genes. You adopt your religion from your parents or someone else, at some stage in life. Sometimes the process is gradual and mostly involuntary. Sometimes it is a sudden decision, voluntary.
It is savarkar who held the view that Brahminism (which he mistakenly and deliberately equated to Hinduism)was biologically acquired. At the root of such views lies not merely ignorance, but the despicable evil of racism.