Define the purpose before comparing gene counts
Genetic testing may investigate the cause of an illness, assess inherited susceptibility or identify a variant that could be passed to a child. These are different purposes, with different tests and interpretations. A risk package for an apparently healthy person is not equivalent to a diagnostic investigation prompted by symptoms. Words such as 'whole' or 'premium' do not mean every disease can be predicted.
Prepare your medical history and the ages at which important conditions were diagnosed in relatives. Ask what would change after a positive, negative or uncertain result. It is reasonable to have counseling before deciding whether to provide a sample.
Whole-exome sequencing is not whole-genome coverage
Whole-exome sequencing primarily reads protein-coding regions, which represent only part of human DNA. It differs from whole-genome sequencing. Neither the word 'whole' nor a large data file guarantees that every relevant change will be detected or understood. Scientific knowledge about disease-associated variants continues to develop.
Ask the laboratory what it actually analyzes, what may be missed, how findings are classified and whether reinterpretation is offered later. Discuss the possibility of findings unrelated to your original question and the choices available to you. A clearly explained scope is more useful than a gene-count headline alone.
Sources: [2] MedlinePlus Genetics / National Library of Medicine
APOE informs risk; it does not establish a diagnosis
The APOE ε4 variant is associated with a higher risk of late-onset Alzheimer's disease. Some carriers never develop the disease, and people without the variant can develop it. A genotype alone cannot establish whether someone currently has Alzheimer's disease or reliably announce when symptoms will appear. It is not a replacement for an assessment of cognitive symptoms.
If memory or thinking has changed, describe the changes to a clinician instead of waiting for a screening package. If you have no symptoms, discuss the emotional and family implications of learning a risk result, and what practical actions would follow.
Sources: [3] MedlinePlus Genetics / National Library of Medicine
Results are not simply 'disease' or 'no disease'
A negative result means the test did not identify a reportable relevant change within its scope and current knowledge. It does not exclude every genetic explanation. A variant of uncertain significance, or VUS, means the evidence is insufficient to settle its meaning; it cannot confirm or rule out a diagnosis.
Review the original report with an appropriately qualified genetics professional, including the medical and family context. Ask whether confirmation, specialist referral or later reinterpretation is needed, and who will contact you. Do not make medication changes or irreversible preventive decisions on the strength of an uncertain result alone.
Sources: [4] MedlinePlus Genetics / National Library of Medicine
Resolve privacy and follow-up questions before sampling
Genetic information can have implications for relatives as well as the person tested. Read the provider's consent and data policies. Ask who stores the sample, raw data and report; how long they are retained; whether third parties or researchers receive them; and how deletion or withdrawal requests are handled. Do not assume one country's protections automatically apply elsewhere.
For an initial price inquiry, avoid sending complete raw genetic files or relatives' reports before a secure, necessary transfer is agreed. Confirm whether counseling, confirmation tests and later reinterpretation cost extra. This article does not promise any laboratory's scope or services.
