HYAL2 and mitral atresia disorder: This study also identified the first 3 individuals with a loss-of-function HYAL2 variant in trans with a missense HYAL2 variant (Individuals 3, 4, and 5) who notably exhibited cardiac anomalies at the more severe end of the spectrum (coarctation of the aorta, mitral valve atresia), with 1 also having severe myopia.