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Updated: Jun 14, 2026

Enrichment of Mammalian Tissues and Xenopus Oocytes with Cholesterol
Published on: March 25, 2020
A SNP of NPC1L1 affects cholesterol absorption in Japanese
Tomomi Maeda1, Akira Honda, Toshio Ishikawa
1Department of Internal Medicine, Teikyo University School of Medicine, Tokyo, Japan. a.fenton@liverpool.ac.uk
Aim:
Ezetimibe is known to target Niemann-Pick Type C1 Like1 (NPC1L1), a key protein in intestinal cholesterol absorption, and thus to decrease serum LDL-cholesterol (LDL-C) levels. The response of serum LDL-C levels to ezetimibe was reported to differe among NPC1L1 haplotypes.We analyzed NPC1L1 genotypes in Japanese and investigated differences in markers of cholesterol synthesis/absorption among the genotypes.
Methods:
Blood samples were collected from 42 adult volunteers to measure markers of cholesterol synthesis (lathosterol) and absorption (sitosterol and campesterol) by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Based on a study by Hegele RA et al. in Canada, we selected three SNPs (1735 C>G, 25342 A>C and 27677 T>C (numbers relative to the transcription start site)) and analyzed them using PCR-RFLP.
Results:
The frequencies of genotypes were as follows: 1735 C/G (46%)>C/C (35%)>G/G (19%), 25342 A/A (97%)>A/C (3%)>C/C (0%) and 27677 T/T (97%)>T/C (3%)>C/C (0%). Serum campesterol levels were significantly higher in the 1735 G/G group than 1735 C/G+C/C group, but lathosterol levels showed no significant differences between the genotypes.
Conclusion:
Our results revealed differences in the frequency of the NPC1L1 polymorphism between Japanese and Canadians. In Japanese, the 1735 G/G group showed enhanced cholesterol absorption from the intestine, as compared to the 1735 C/G+C/C group.
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