De Barsy syndrome and ATP6V0A2-CDG

We read with interest the nice review of Morava et al¹ on the autosomal recessive cutis laxa syndromes. The authors mention the De Barsy syndrome and state that the genetic background of the De Barsy syndrome has not yet been identified. However, in the paper by Kornak et al² on impaired glycosylation and cutis laxa caused by mutations in ATP6V0A2 (ATP6V0A2-CDG according to the novel nomenclature^{3, 4}), one of the patients (see patient CoFe in Table 1 of Kornak et al²) shows the full clinical picture of the De Barsy syndrome, including cutis laxa, facial dysmorphy, dwarfism, psychomotor retardation, dystonia, congenital hip dysplasia, and corneal dystrophy necessitating repeated corneal transplantation. These data suggest that a subgroup of patients with De Barsy syndrome⁵ belongs to the spectrum of ATP6V0A2-CDG. Another cause of De Barsy syndrome has very recently been identified as mutations in PYCR1, coding for a mitochondrial enzyme involved in proline metabolism.⁶ Therefore, we recommend a systematic screen for ATP6V0A2-CDG and for mutations in PYCR1 in patients with De Barsy syndrome.