Is transient tachypnoea of the newborn associated with polymorphisms in the epithelial sodium channel encoding gene? Investigation of the second transmembrane spanning domain of the alpha subunit.
OBJECTIVE
We hypothesized that polymorphisms in the region encoding for the second transmembrane spanning domain of the epithelial sodium channel may be one factor in the pathogenesis of transient tachypnoea of the newborn. We thus searched for polymorphisms in this region in neonates with transient tachypnoea of the newborn. We also investigated samples from preterm neonates with respiratory distress syndrome, as dysfunction of the epithelial sodium channel might also increase the risk for developing respiratory distress syndrome and influence its course.


METHODS
We used denaturing gradient gel electrophoresis to detect sequence variants in exon 12 and 13 of the epithelial sodium channel. Forty-three neonates with transient tachypnoea of the newborn (gestational age [mean +/- SD]: 38.3 +/- 1.2 completed weeks; birthweight: 3088 +/- 426 g), 57 neonates with RDS (gestational age: 29.6 +/- 3.5 completed weeks; birthweight: 1272 +/- 638 g), and 50 healthy controls were enrolled prospectively.


RESULTS
We did not detect any polymorphism. Neither did confirmative sequencing of this region in 16 neonates with transient tachypnoea of the newborn reveal any polymorphism.


CONCLUSIONS
We conclude that reasons other than polymorphisms in the second transmembrane spanning domain cause transient tachypnoea of the newborn.
Landmann
E
E
Paediatric Centre, Department of Paediatrics and Neonatology, Justus-Liebig-University, Giessen, Germany. eva.landmann@paediat.med.uni-giessen.de
Schmidtpott
M
M
Tutdibi
E
E
Gortner
L
L
D000595:Amino Acid Sequence; D015180:Electrophoresis, Gel, Two-Dimensional; D053503:Epithelial Sodium Channels; D005091:Exons / Q000235:genetics; D006801:Humans; D007231:Infant, Newborn; D007234:Infant, Premature; D008168:Lung / Q000196:embryology / Q000502:physiology*; D016297:Mutagenesis, Site-Directed; D011110:Polymorphism, Genetic; D012127:Respiratory Distress Syndrome, Newborn / Q000235:genetics*; D015222:Sodium Channels / Q000235:genetics*
D053503:Epithelial Sodium Channels; D015222:Sodium Channels