Identification of the nucleotide substitution that generates the fourth polymorphic site in human deoxyribonuclease I (DNase I).
In addition to the three polymorphic sites responsible for protein polymorphism, a new polymorphic site has been identified in intron 7 of the human deoxyribonuclease I (DNase I) gene. Three phenotypes were observed on single-strand conformational polymorphism analysis of a 266-bp polymerase chain reaction-amplified fragment containing exon 7 and part of intron 7 of the human DNase I gene. DNA sequencing analysis demonstrated that a C-G substitution occurred at position 1978 in intron 7. This substitution was confirmed by restriction fragment length polymorphism analysis, since a new Msp1 site is created by the substitution. Population and family studies showed that the inheritance of the genotypes for DNase I C1978G polymorphism is controlled by two codominant alleles, tentatively designated DNASE1*1978C and *1978G. The gene frequencies in a Japanese population were significantly different from those in a Caucasian (German) population. The C1978G polymorphism is in linkage disequilibrium with the common DNase I protein phenotypes 1, 1-2, and 2.
Iida
R
R
Department of Legal Medicine, Fukui Medical School, Japan.
Yasuda
T
T
Takeshita
H
H
Tsubota
E
E
Yuasa
I
I
Nakajima
T
T
Kishi
K
K
D001483:Base Sequence; D017931:DNA Primers; D003850:Deoxyribonuclease I / Q000235:genetics*; D005091:Exons; D005838:Genotype; D006801:Humans; D007438:Introns; D008969:Molecular Sequence Data; D010641:Phenotype; D017354:Point Mutation; D016133:Polymerase Chain Reaction; D012150:Polymorphism, Restriction Fragment Length; D018807:Polymorphism, Single-Stranded Conformational
D017931:DNA Primers; D003850:Deoxyribonuclease I