Rapid detection and prevalence of cholesteryl ester transfer protein deficiency caused by an intron 14 splicing defect in hyperalphalipoproteinemia.
A deficiency of plasma cholesteryl ester transfer protein (CETP) is one of the genetic causes of increased serum high density lipoprotein (HDL)-cholesterol levels (hyperalphalipoproteinemia). A splicing defect (G-->A mutation) at the +1 position of intron 14 of the human CETP gene is a common mutation in the Japanese CETP deficiency. A rapid screening method for the splicing defect by means of primer-specified restriction map modification was described. The frequency of the mutation in hyperalphalipoproteinemia was determined, and its frequency in the general population was estimated. During polymerase chain reaction (PCR) with a modified primer, a novel NdeI restriction endonuclease site was created from the mutated allele in the PCR products, which could be visualized after electrophoresis of the digested products. As a result, 21 of 121 unrelated hyperalphalipoproteinemic subjects with HDL-cholesterol > or = 60 mg/dl (1.55 mmol/l), were found to have the G-->A mutation. Of the 21 individuals, 8 were found to be homozygous for the mutation. Allele frequency of the mutation was 1.5% (1/68), 2.8% (2/72), 7.1% (4/56), and 47.8% (22/46) in the groups with HDL-cholesterol levels of 60-79 mg/dl, 80-99 mg/dl, 100-119 mg/dl, and > or = 120 mg/dl, respectively. Based on the percentage of the area under the computed normal distribution curve of serum HDL-cholesterol, the frequency of the mutated allele in the general population was estimated to be 0.81% from the present results. This rapid detection method facilitates large-scale screening of CETP deficiency caused by the splicing defect. The mutation was frequent in Japanese subjects with hyperalphalipoproteinemia, especially in the group with HDL-cholesterol > or = 120 mg/dl.
Inazu
A
A
Second Department of Internal Medicine, School of Medicine, Kanazawa University, Japan.
Koizumi
J
J
Haraki
T
T
Yagi
K
K
Wakasugi
T
T
Takegoshi
T
T
Mabuchi
H
H
Takeda
R
R
D000328:Adult; D000368:Aged; D001483:Base Sequence; D002352:Carrier Proteins / Q000097:blood / Q000235:genetics*; D053480:Cholesterol Ester Transfer Proteins; D008076:Cholesterol, HDL / Q000097:blood*; D005260:Female; D005787:Gene Frequency; D006580:Genetic Carrier Screening / Q000379:methods*; D006023:Glycoproteins; D006801:Humans; D007438:Introns / Q000235:genetics*; D007564:Japan / Q000208:ethnology; D008297:Male; D008875:Middle Aged; D008969:Molecular Sequence Data; D017354:Point Mutation / Q000235:genetics*; D016133:Polymerase Chain Reaction; D015183:Restriction Mapping
C506642:CETP protein, human; D002352:Carrier Proteins; D053480:Cholesterol Ester Transfer Proteins; D008076:Cholesterol, HDL; D006023:Glycoproteins