Most of the patients diagnosed with P5CS deficiency and PYCR1 deficiency suffered from cutis laxa, and these disorders are therefore classified as autosomal recessive cutis laxa syndromes (PSCS AR cutis laxa type 2b, type 3a and type3b, OMIM 138250). The gene discussed is PYCR1; the disease is hyperinsulinemic hypoglycemia, familial, 4.