I'm sure this is a basic question, but I couldn't find an answer anywhere. Let's say I'm provided with the location of a nucleotide as location as FGFR3:c.1843-35A>T. What does "1843-35" mean?
As 'c.' stands for 'coding' sequence (instead of 'g.' for 'genomic'), according the HGVS guidelines it denotes the A to T substitution at nucleotide -35 of an intron (in the coding DNA positioned between nucleotides 1842 and 1843).