title: Human SP-A: genotype and single-strand conformation polymorphism analysis.
abstract: We have previously characterized two surfactant protein A (SP-A) cDNAs termed 1A and 6A, as well as a 6A allelic variant termed 6A1. These sequences are quite heterogeneous at the 3' untranslated region (3'UT). Differences between 6A and 6A1 alleles include an 11-bp insertion/deletion 407 bases downstream from the start of the translation termination codon and a base pair polymorphism (C or G) in exon 1 (position 1,193; White, Damm, Miller, Spratt, Schilling, Hawgood, Benson, and Cordell. Nature Lond. 317: 361-363, 1985). The 11-bp (GCCCACTGCCT) segment is present in 6A1 and absent in 6A. The 6A/6A genotype, in a small number of specimens, showed a trend toward a higher frequency in the black Nigerian population compared with Caucasians. In this report, we examine the frequency of the 6A genotype in a larger number of samples from Caucasians and black Nigerians as well as the meiotic stability of the 3'UT heterogeneity. Slot-blot analysis and allele-specific oligonucleotide probes have confirmed that the 6A/6A genotype is more frequent in the Nigerian population. Single-strand conformation polymorphisms in the 3'UT appear to be stably inherited by members of a three-generation family, suggesting that these nucleotide variants represent natural polymorphisms in the population.
authors.affiliation: Department of Cellular and Molecular Physiology, Pennsylvania State University College of Medicine, Hershey 17033.
authors.forename: L
authors.initials: L
authors.lastname: Krizkova
authors.forename: R
authors.initials: R
authors.lastname: Sakthivel
authors.forename: S A
authors.initials: SA
authors.lastname: Olowe
authors.forename: P K
authors.initials: PK
authors.lastname: Rogan
authors.forename: J
authors.initials: J
authors.lastname: Floros
mesh_terms: D001483:Base Sequence; D044383:Black People / Q000235:genetics; D004247:DNA / Q000097:blood / Q000235:genetics / Q000302:isolation & purification; D017931:DNA Primers; D005260:Female; D005787:Gene Frequency; D008040:Genetic Linkage; D014644:Genetic Variation; D005838:Genotype; D006023:Glycoproteins / Q000235:genetics; D006801:Humans; D008297:Male; D008540:Meiosis; D008969:Molecular Sequence Data; D009549:Nigeria; D009838:Oligodeoxyribonucleotides; D010375:Pedigree; D016133:Polymerase Chain Reaction / Q000379:methods; D011110:Polymorphism, Genetic; D011510:Proteolipids / Q000096:biosynthesis / Q000235:genetics*; D037662:Pulmonary Surfactant-Associated Protein A; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants / Q000096:biosynthesis / Q000235:genetics*; D044465:White People / Q000235:genetics
chemical_list: D017931:DNA Primers; D006023:Glycoproteins; D009838:Oligodeoxyribonucleotides; D011510:Proteolipids; D037662:Pulmonary Surfactant-Associated Protein A; D037661:Pulmonary Surfactant-Associated Proteins; D011663:Pulmonary Surfactants; D004247:DNA