A PSEN2 genetic test checks for disease-causing changes in PSEN2, one of three genes tied to early-onset Alzheimer's disease. For a second opinion, it runs inside a dementia panel, self-pay runs $100 to over $2,000, coverage is narrow, and referrals need specific questions.
PSEN2 sits on chromosome 1 with APP and PSEN1. Early onset means symptoms before age 65, and a carrier parent has a 50/50 chance of passing the variant to a child, according to the NIA genetics fact sheet. Testing usually enters the picture when personal and family history suggest dominant early-onset disease and another diagnosis or plan is under review.
Medical information disclaimer: This article is for general educational purposes only and does not provide medical advice, diagnosis, or treatment. Always consult a physician or other qualified health professional about symptoms, medications, tests, or treatment decisions.
Table of Contents
- What PSEN2 testing checks
- When a second opinion considers it
- What it costs and what plans cover
- Referral and consent questions to ask
What PSEN2 testing checks
PSEN2 testing looks for sequence changes plus deletions and duplications. Labs order it as sequencing plus deletion/duplication analysis, often inside a broader dementia panel. Examples include dementia panels that also cover ALS, frontotemporal dementia, and APOE.
A positive result can explain dominant early-onset disease in a family. A negative panel does not rule out dementia. Clinical studies report only 5-13% of early-onset cases receive a molecular diagnosis from APP/PSEN1/PSEN2 testing, with PSEN2 explaining a small minority, according to the University of Pennsylvania genomic medicine page.
When a second opinion considers it
Guidelines point to family pattern more than symptoms alone. The 2011 ACMG/NSGC joint guideline says APP/PSEN1/PSEN2 testing may be considered with dominant early-onset personal and family history. It prefers testing a living affected relative first to confirm the familial variant.
That order matters for second opinions. An affected parent or sibling with early-onset dementia gives the clearest sample. Testing an unaffected person first can produce uncertain or unhelpful results. Bring pedigrees, ages at onset, prior workup, and any prior genetic reports to the visit.
What it costs and what plans cover
Out-of-pocket clinical prices range from about $100 to over $2,000 without insurance, according to the Medicare.org price overview. Panel size, lab, and self-pay terms drive the spread. Ask for the cash price, billing code, and whether APOE or other genes add charges.
Coverage is tighter than testing availability. HealthPartners covers PSEN1/PSEN2/APP sequencing only with family dementia history consistent with autosomal-dominant inheritance plus required pre- and post-test counseling, while many plans call broader Alzheimer genetic screening investigational or not medically necessary, according to HealthPartners coverage criteria. Get prior authorization in writing before blood is drawn. Ask what counts as qualifying family history and what denial options exist.
Referral and consent questions to ask
Counseling is part of the test, not an add-on. The Alzheimer's Association calls for formal genetic counseling with informed consent before testing and in-person disclosure after, including emotional, family, and insurance effects.
Use the referral to lock in that support. Federal GINA protections generally exclude life, disability, and long-term-care insurance, so ask how that gap affects your household before consent.
- Will the referral include a genetics counselor for pre- and post-test visits?
- Which affected relative will be tested first, and is that person available?
- What genes and deletion/duplication analysis does the panel cover?
- What are the prior-authorization criteria and self-pay price?
- How will results be disclosed, and what family and insurance issues will counseling address?
