Nowaday the Single nucleotide polymorphism testing is becoming more important. ApoE testing can be used to predict risk before symptoms appear. APOE-4 This is used to assess risk levels, plan prevention, screening frequency, surveillance, and to recommend better treatment.
APOE genetic testing
It will let us know if we might inherit a risk of the disease from our parents.
There are three types of alleles: APOE-2, APOE-3, and APOE-4. Most are APOE-3 formats.
If anyone inherits APOE-2, which is considered a protective gene, it is considered lucky, but it is also very rare.
While APOE-4 is considered a risk-factor gene, it doesn’t mean that it has to result in a disease developing as some people have APOE-4 but don’t have the disease.
What is Apolipoprotein E?
Apolipoprotein E (APOE) is a protein that plays a role in the transport of lipid fats and substances to or from organs. Therefore, people with a form of APOE that is less able to remove this type of protein, resulting in a greater accumulation of amyloid beta in neurons, have a higher risk of developing Alzheimer’s disease.
Studies have found that the accumulation of amyloid protein is because APOE plays an important role in helping remove amyloid beta protein from cells. Each form of APOE synapses has a different ability to clear amyloid beta protein. Therefore, people with a form of APOE that is less able to remove this protein, causing more amyloid beta to build up in nerve cells, have a higher risk of developing Alzheimer’s disease.
There are 3 types of ApoE: ApoE2, ApoE3 and ApoE4, in which we will inherit 1 pair of ApoE from mom and dad. Most people have genes of E3/E3 or E3/E2, E3/E4.
The pattern of APOE associated with the risk of developing Alzheimer’s disease can be summarized as follows:
- E3/E3 has an Alzheimer’s disease risk equivalent to the average of the general public.
- E2/E2 or E2/E3 have a 0.6 times lower risk of developing Alzheimer’s disease than average.
- E2/E4, E3/E4 or E4/E4 are 15-20 times more likely to develop Alzheimer’s disease than average.
Benefits of ApoE gene testing
- Know the risk of Alzheimer’s disease in the future
- Assist doctors in planning effective care.
- Useful in lifestyle modification
- Useful in treatment with lipid-lowering drugs
Alzheimer's: Know the risks before it's too late
What causes Alzheimer's disease?
Alzheimer’s is the most common cause of dementia, accounting for up to 60-80% of all dementia.
- Amyloid plaque, an abnormally stored protein
- Acetylcholine, which is a neurotransmitter produced within the brain, helps in muscle movement, thinking, memory processes, and temporary storage of information. Decreased levels of acetylcholine can lead to brain cell deterioration.
Symptoms of Alzheimer's disease
- In the first stage, there will be more amnesia and forgetfulness, such as forgetting events that just happened, forgetting conversations, obsessive-compulsive thoughts. Asking the same question several times. Repeating the same story. Difficulty thinking of words, forgetting names of places and objects, confusion of directions, and mood swings.
- In the middle stage, there will be more memory and learning impairments, such as not being able to remember people’s names. Difficulty speaking, numbness. The date and time are unknown. Trouble using tools such as telephones, televisions, electrical appliances, as well as symptoms of misplacement, wandering in the wrong direction, walking aimlessly out of the house, and starting to hallucinate.
- Final phase. Symptoms will be more severe, hallucinations, delusions, fear, difficulty chewing food and swallowing, weight loss, aggressive behaviour, urinary and faecal incontinence. Inability to perform daily routine alone. Refusing to accept someone to help. Unable to walk. Difficulty communicating.
Risk factors
- Age over 65 years.
- Family history and genetics, if a person in the family suffers from this disease, it increases the risk of developing Alzheimer’s disease.
- Severe head injury is at risk of Alzheimer’s disease.
- Females are at greater risk of developing this disease than males.
Alzheimer's disease screening program
Can be examined from blood and buccal mucosa.
- APOE genotype for Alzheimer’s disease (Alleles E2,E3,E4)
