Background. Adenosine triphosphate-binding cassette subfamily A member 3 (ABCA3) gene variants, which cause severe respiratory distress syndrome (RDS) in term newborns, can cause death, especially due to the lack of congenital surfactant protein. The relationship between the types, pathophysiology and effects of ABCA3 gene variants on surfactant metabolism and the clinical phenotype have not yet been fully clarified, but the ABCA3 genotype is known to affect clinical severity. Case. In our study, in a term newborn with a diagnosis of RDS resulting in death, we detected the c.3677 T> C (p.Leu1226Pro) variant homozygous variant in the ABCA3 gene according to the NM_001089.3 transcript, which, to our knowledge, was identified for the first time in the literature. Conclusions. We consider that this case report contributes to the literature on RDS by showing the presence of c.3677 T> C (p.Leu1226Pro), a new homozygous variant of ABCA3 in our patient.
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