Family Hx/Genetic Pedigrees Flashcards
Why family hx?
- identify hereditary disorders
- determine inheritance patterns
- determine recurrence risks
- identify at-risk individuals
- identify individuals not at risk
SCREEN Mnemonic
SC: Some Concerns about disease that run in family
R: Reproduction problems
E: a history of Early disease, death, or disability in family
E: Ethnicity of patient
N: Non-genetic risk factors or medical conditions that run in family
SC of SCREEN
Some Concerns about disease in family
R of SCREEN
Reproduction problems
First E of SCREEN
Early diseases, disability or death in family
Second E of SCREEN
Ethnicity of Patient
N of SCREEN
Non-genetic risk factors or medical conditions in family
Barriers to Family Hx Collection
- lack of time
- incomplete records
- inaccessible family members
- blame and guilt
- incorrect or vague diagnoses
- multiple caretakers for child
- poor follow-through on questions
- fear of discrimination/stigmitization
- lack of physician reimbursement
- difficulty finding family hx in pt’s med records
- difficulty entering and updating info into EMR
Family Hx Red Flags
if you hear “too” or “two” that usually means genetic factors because its happened many times
*other common red flags include:
- reproductive or prenatal history issues
- early or unexpected death
- cognitive and/or behavioral issues
- growth and statue disorders
- sensory organ deficits
How to Construct a Pedigree
- start w/core family
- add aunts/uncles
- add cousins
- add grandparents and their siblings
- identify individuals w/genetic conditions to better understand disorders in fam
Common Inheritance Patterns
- Autosomal Dominant
- Autosomal Recessive
- X-Linked Recessive
- Multifactorial
Autosomal Dominant Pattern
often seen in consecutive generations in both males and females
- presentation of genetic disorder can vary among affected family members
- male-to-male transmission implies autosomal dominant transmission
Autosomal Recessive Pattern
usually not found in every generation of family
- sometimes affects only one member of an entire extended family
- can be in both males and females
X-Linked Recessive Pattern
only males in the extended family are affected by a genetic condition, or the condition is more severe in males than females
Multifactorial Pattern
set pattern is not evident so multiple individuals can be affected in multiple generations
- often indicates a combination of genetic and environmental factors
