Autosomal dominant
A pattern of inheritance in which a single altered copy of a gene — inherited from either parent — is enough to cause or raise the risk of a condition. A child of an affected parent has a one-in-two chance of inheriting the variant. Many hereditary cancer syndromes, including those linked to BRCA1, BRCA2, and Lynch syndrome, follow this pattern.
Autosomal recessive
A pattern in which a condition appears only when both copies of a gene are altered, so a person inherits one altered copy from each parent. Parents who each carry a single copy usually have no symptoms, which is why a recessive condition can surface in a family that seemed to have no history of it.
BRCA1 and BRCA2
Two genes that normally help repair damaged DNA. Inherited variants in either gene raise the lifetime risk of breast, ovarian, and several other cancers, and pass down in an autosomal-dominant pattern. A family history of these cancers — especially at younger ages or across several relatives — is one of the signals clinical guidelines use to decide who to refer to a genetic counselor.
De-identification
Removing or replacing the details that tie health information to a specific person — names, dates, contact details, record numbers — so the remaining data is harder to trace back. Before Relative Health Report sends family history to an AI model, your device replaces names with relationship terms ("parent", "sibling") and strips common identifiers. The security white paper sets out what the company can and cannot see.
Evidence grade
A label that shows how strong the basis for a recommendation is. In the app, every clinical-sounding insight carries an evidence-grade chip drawn from a published source — a USPSTF grade, an NCCN category, an ACMG referral criterion, or "Pattern-matched" when the insight reflects a pattern that does not map cleanly to one published rule. How we grade insights walks through the full vocabulary.
First-, second-, and third-degree relatives
A way of describing how closely two people are related by blood. First-degree relatives (parents, siblings, children) share about half their DNA on average; second-degree relatives (grandparents, aunts, uncles, half-siblings) share about a quarter; third-degree relatives (first cousins, great-grandparents) share roughly an eighth. Closer relatives carry more weight when a family history is read, which is why the science page explains how the degree of relationship shapes an insight.
Genetic counselor
A health professional trained to assess inherited risk, explain genetic-testing options, and help people make decisions about their care. Relative Health Report does not replace a genetic counselor; it helps you organise the family history one would ask for. The referral criteria the app draws on come from the ACMG and the National Society of Genetic Counselors (NSGC) — see where our insights come from.
GINA (Genetic Information Nondiscrimination Act)
A 2008 U.S. federal law that bars health insurers and employers from using your genetic information or family medical history against you. It does not extend to life, long-term-care, or disability insurance, the military, or employers with fewer than 15 employees — a gap worth understanding before you share family history with a clinician. Our methodology page explains the gap in full.
Hereditary cancer syndrome
An inherited condition that raises the risk of one or more cancers, usually caused by a variant in a single gene passed down through a family. Lynch syndrome and hereditary breast and ovarian cancer (linked to BRCA1 and BRCA2) are common examples. Recognising the family-history patterns these syndromes produce is part of why clinical guidelines ask for a three-generation pedigree.
Lynch syndrome
An inherited condition that raises the risk of colorectal, endometrial, and several other cancers, often at younger ages than usual. It is one of the more common hereditary cancer syndromes and follows an autosomal-dominant pattern. Criteria such as the NCCN guidelines use family-history patterns to decide who should be assessed for it.
NCCN category
A rating from the National Comprehensive Cancer Network that shows how much evidence and expert agreement stand behind a recommendation, from Category 1 (high evidence, uniform consensus) through 2A and 2B to 3 (major disagreement). The app surfaces NCCN categories as evidence-grade chips on the insights they support.
Pedigree
A standardised family tree that records health information — who is related to whom, who has had which conditions, and at what age. Clinicians read a pedigree to spot inherited patterns that are not obvious from one person’s history. Relative Health Report builds one from the family members and conditions you enter; the science page describes the standard it follows.
Penetrance
The chance that a person carrying a particular gene variant actually develops the associated condition. High penetrance means most carriers are affected; reduced penetrance means a variant can pass silently through a generation, which is why a condition sometimes appears to "skip" relatives. Penetrance is one reason family history points to probability rather than certainty.
Proband
The person a family-history record is built around — usually you. In a pedigree, the proband is the starting point from which every other relationship (parent, sibling, cousin) is described.
Three-generation pedigree
A family health history that reaches across three generations — grandparents; parents and their siblings; and you, your siblings, and your children. It is the standard clinical bodies such as the NSGC, NCCN, and AAFP recommend, because three generations are usually enough to reveal an inherited pattern that a single generation would hide. The science page explains why.
USPSTF grade
A letter grade from the U.S. Preventive Services Task Force that summarises whether a screening or preventive service is worth doing: A and B mean recommended, C means offer it selectively, D means recommended against, and I means the evidence is insufficient to judge. The app shows USPSTF grades as evidence-grade chips so you can see the strength behind a screening prompt.
Zero-knowledge
A design in which the company that runs a service cannot read the data you store in it. In Relative Health Report, your family health information is encrypted on your device under a key derived from your passphrase — a key the company never receives — so the servers hold only ciphertext. The security white paper sets out exactly what each party can and cannot see.
Want the detail behind these terms? Read the science behind the insights, how we build them, and how your data is protected.