They can have the name but they can not have our genes. I have a "Singh" in my name and I am 6'1" and fair. We have recessive genes for green eyes as well(My grandfather had green eyes).
At the same time we have a Singh in our office. Half as short as me, dark hair and dark eyes. 10/10 Bimaru Bhangi looks. He may very well be cleaning shit after office hours but I am not sure.