ABCC6 and Pseudoxanthoma elasticum: WES analysis of Patient 50, presenting severe bilateral sensorineural HL and cutaneous signs of pseudoxanthoma elasticum, highlighted the presence of a known heterozygous variant in the WFS1 gene [29], associated with Deafness, autosomal dominant 6/14/38 (MIM: # 600965) and an already-reported homozygous variant in the ABCC6 gene [30], causative of pseudoxanthoma elasticum (MIM: # 264800).