SFTPA1 and newborn respiratory distress syndrome: In addition, our previous studies found that the genotype and allele frequencies of SP-A1 (SNP) locus (rs1059047, and rs1136450) were not associated with the occurrence of RDS in Mongolian premature infants, and the haploid 6A2 of SP-A1 allele was the susceptible gene of RDS in Mongolian premature infants, and haploid 6A was the protective gene (28).