The identification of a novel homozygous FBLN5:c.53del frameshift variant in cutis laxa type 1A and a heterozygous ATM:c.4828dup frameshift variant in ataxia telangiectasia demonstrates the value of whole genome sequencing followed by Sanger confirmation in clarifying atypical and overlapping phenotypes. Here, ATM is linked to Ataxia-telangiectasia.