A __ is a pictorial representation of a family history that outlines the inheritance of specific characteristics. A consanguinity
B proband
C genealogy tree
D carrier
E pedigree
The correct answer and explanation is:
The correct answer is E) pedigree.
A pedigree is a pictorial representation of a family history that outlines the inheritance of specific characteristics or traits over several generations. It is commonly used in genetics and medicine to track the transmission of genetic disorders or traits within a family. The diagram shows the relationships among family members and indicates which individuals express or carry a particular trait.
Pedigrees use standardized symbols to represent males, females, affected individuals, carriers, and unknown statuses. Squares typically represent males, and circles represent females. Shaded symbols indicate individuals who express the trait or condition of interest, while half-shaded or other notations can show carriers—people who carry a recessive gene but do not express the trait. Lines connect individuals to show relationships, such as parents and offspring, or marriages.
The main purpose of a pedigree is to help geneticists, physicians, and counselors understand the mode of inheritance of a genetic trait or disease. This includes identifying whether the trait is dominant, recessive, sex-linked, or mitochondrial. By analyzing a pedigree, healthcare professionals can estimate the risk that an individual will inherit or pass on a genetic disorder. It is an important tool in genetic counseling, which provides information and support to families affected by or at risk for genetic conditions.
Other terms mentioned in the question:
- Consanguinity refers to the genetic relationship between individuals who share a common ancestor, such as cousins. It is not a diagram but a concept related to relatedness and genetic risks.
- Proband is the individual in a family who is first identified with a genetic disorder or trait and through whom the family study begins.
- Genealogy tree is a general family tree showing ancestry but usually does not focus on specific inherited traits.
- Carrier is a person who has one copy of a recessive gene mutation but does not show symptoms of the genetic condition.
In summary, a pedigree is the specific tool used to visually map the inheritance of traits within families, making it essential in genetics and medicine.