Apolipoprotein E (Apo E) genotyping
What is analysed?
Apolipoprotein E (Apo E) is a protein that helps transport lipids (fat) and cholesterol.
There are several isoforms (variants) of the Apo E protein, but three major ones - Apo E2, Apo E3, and Apo E4 - are most commonly found in humans. Everyone possesses a pair of Apo E genes that forms different combinations, for example E3/E3, E2/E4 etc.
Apo E genotyping is an analysis that examines specific variations in the APOE gene.
What does the result mean?
The result indicates which isoform of the APOE gene a patient carries.
Specific and different combinations of isoforms are associated with varying risks for cardiovascular and neurodegenerative conditions.
Why conduct the analysis?
Apo E genotyping is conducted to help diagnose Type III hyperlipoproteinaemia, a rare genetic disorder that affects lipid metabolism, leading to abnormal elevations in cholesterol and triglyceride levels in the blood.
When to conduct the analysis?
Apo E genotyping is conducted in various clinical scenarios:
When high cholesterol and triglyceride concentrations are suspected to be caused by a genetic disorder. When types of xanthomas (raised yellow patches) on the skin are observed.What sample is required?
A blood sample is required. The blood is taken from a vein, usually in the arm.
Is any prior preparation necessary?
No prior preparation is required.
How is it performed?
The sample is sent to a laboratory, where it is analysed using molecular techniques such as polymerase chain reaction (PCR) and DNA sequencing to identify the specific isoform of the Apo E gene.