Surfactant protein (SP) B associations and interactions with SP-A in white and black subjects with respiratory distress syndrome.
BACKGROUND
The etiology of respiratory distress syndrome (RDS) is multifactorial and/or multigenic. Surfactant protein A (SP-A) and/or SP-B genetic variants have been identified as risk or protection factors for RDS.


METHODS
We genotyped subjects with and without RDS for the SP-B intron 4 size variants (invariant (inv), deletion (del), insertion (ins) and for four (-18 (A/C), 1013 (A/C), 1580 (C/T), 9306 (A/G)) SP-B single nucleotide polymorphisms (SNP), to study case-control associations in black and white subjects. We also determined whether specific SP-B variants interact with RDS susceptibility or protective SP-A variants to enhance or reduce risk for RDS.


RESULTS
Based on odds ratio: (1) the SP-B intron 4 del variant in white subjects is more of an RDS risk factor for males and for subjects of 28 weeks <gestational age (GA)<33 weeks; (2) the SP-B intron 4 ins variant in black subjects is more of an RDS risk factor in females; (3) in white subjects, SP-A1 (6A(2)/6A(2)) or SP-A2 (1A(0)/1A(0) or 1A(0)/*) genotypes in subjects of certain GA and with a specific SP-B genotype (9306 (A/G) or del/*) are associated with an enhanced risk for RDS; (4) in black subjects, SP-A1 (6A3/6A(3) or 6A(3)/*) genotypes in subjects of 31 weeks < or = GA < or = 35 weeks and with the SP-B (1580 (T/T)) genotype are associated with a reduced risk for RDS.


CONCLUSIONS
The SP-B polymorphisms are important determinants for RDS. These may identify differences between black and white subjects, as well as, between males and females regarding the risk for RDS. Furthermore, SP-A susceptibility or protective alleles, in specific SP-B background, are associated, based on OR, with an increased or reduced risk for RDS.
Floros
J
J
Department of Cellular and Molecular Physiology, The Milton S. Hershey Medical Center, Pennsylvania State University College of Medicine, PO Box 850, 500 University Drive, Hershey, PA 17033, USA. jfloros@psu.edu
Fan
R
R
Diangelo
S
S
Guo
X
X
Wert
J
J
Luo
J
J
D000483:Alleles; D044383:Black People / Q000235:genetics; D005260:Female; D005819:Genetic Markers; D005838:Genotype; D005865:Gestational Age; D006801:Humans; D007231:Infant, Newborn; D007438:Introns / Q000235:genetics; D016015:Logistic Models; D008297:Male; D016017:Odds Ratio; D016133:Polymerase Chain Reaction; D011110:Polymorphism, Genetic; D011510:Proteolipids / Q000235:genetics*; D037662:Pulmonary Surfactant-Associated Protein A; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants / Q000235:genetics*; D012127:Respiratory Distress Syndrome, Newborn / Q000208:ethnology / Q000235:genetics* / Q000378:metabolism; D012307:Risk Factors; D044465:White People / Q000235:genetics
D005819:Genetic Markers; D011510:Proteolipids; D037662:Pulmonary Surfactant-Associated Protein A; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants; C445842:SFTPA1 protein, human; C445843:SFTPA2 protein, human