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Updated: May 7, 2026
07:54
Cholesterol Efflux Assay
Published on: March 6, 2012
A frameshift mutation in the human apolipoprotein A-I gene causes high density lipoprotein deficiency, partial
H Funke1, A von Eckardstein, P H Pritchard
1Institut für Klinische Chemie und Laboratoriumsmedizin, Universität Münster, FRG.
The Journal of Clinical Investigation
|January 1, 1991
Summary
A genetic defect in apolipoprotein A-I (apo A-I) causes high-density lipoprotein (HDL) deficiency and corneal opacities. This study identified a specific mutation responsible for the condition, distinct from coronary artery disease.
Area of Science:
- Genetics
- Biochemistry
- Ophthalmology
Background:
- High-density lipoprotein (HDL) deficiency is linked to atherosclerosis.
- Defects in HDL apolipoproteins or modifying enzymes may cause deficiency.
- Fish eye disease presents with corneal opacities and absent HDL cholesterol.
Observation:
- A patient with corneal opacities and absent HDL cholesterol was studied.
- Abnormal apolipoprotein A-I (apo A-I) banding and reduced lecithin: cholesterol acyltransferase (LCAT) activity were noted.
- Genetic analysis focused on apo A-I and LCAT genes.
Findings:
- A frameshift mutation in the apo A-I gene was identified in the patient.
- The LCAT gene sequence was normal.
- Mass spectrometry confirmed the presence of mutant apo A-I and absence of normal apo A-I.
Implications:
- A defective apo A-I is identified as the cause of HDL deficiency with corneal opacities.
- This finding clarifies the genetic basis of a specific HDL deficiency disorder.
- Understanding apo A-I defects is crucial for managing related lipid disorders.
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