I'm totally new to genomics. I have come across the words Left Alignment and Right Alignment. I know what is alignment but I don't know the difference between left & right alignment. Kindly resolve my doubt. Thanks in advance!
This refers to variants. See this previous post. By definition, a variant is left aligned if and only if it is no longer possible to shift its position to the left while keeping the length of all its alleles constant. See the variant normalization page here.