GUCA1A and respiratory distress syndrome in premature infants: A Japanese study of 1192 IRD families found 3 GUCA1A families,6 a German study reported 8 of 2158 IRD patients,12 and a study of 800 Chinese probands with nonsyndromic IRDs (of whom 481 achieved a positive genetic diagnosis) reported 2 patients with variants in GUCA1A.13