Genetic pedigree and family history Flashcards
what can constructing a pedigree with accurate family history be used for?
Identifying hereditary disorders, determining inheritance patterns, determining recurrence risks, identifying at risk individuals and not at risk individuals
What does the SCREEN Mneumonic stand for?
SC- some concerns about diseases 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
What is the Correct documentation of family history?
Correct diagnosis or disease
Age of onset
Cause of death
Relationships between family members
Whether there is a consanguinity
Ethnic background of both sides
What does Consanguinity mean?
Blood related
What are some barriers for correct family history?
Lack of time
Incomplete records
Inaccessible family members
Incorrect or vague diagnosis
Blame or guilt
Multiple caretakers for child
Poor answer to questions
Fear of discrimination and stigmatization
Lack of physician reimbursement
Difficulty finding family history in patient records
Difficulty entering and updating comprehensive information into EMR
What are red flags in family history?
Too and two
Ex two tumors, two generations, two birth defects
Ex too tall, too short, too early, too many
How many generations in pedigree is ideal?
3
What is the order of making a pedigree
Core family
Aunts uncles
Cousins
Grandparents and siblings
Identify individuals with genetic conditions to understand disorders in family
What are the most common inheritance patterns?
autosomal dominant
autosomal recessive
x-linked recessive
multifactoral
Autosomal dominent
Seen in consecutive generations in females and males
Presentation can vary among those family members who are affected
Male to male transmission implies dominant transmission
Autosomal recessive
Usually not found in every generation of the family and sometimes affects only one member of an entire extended family. Can be males and females
X-linked recessive
If only males in the extended family are affected by genetic condition or condition more severe in males than females than x linked recessive condition should be considered
Multifactoral
Set pattern not evident, so multiple individuals can be affected in multiple generations. Multifactoral conditions can be caused by a combination of genetic and environmental factors
What is the incidence of birth defects?
3%
When can birth defects present?
Later in infancy, childhood, or adulthood
what percent of pediacric hospitalizations are due to genetic causes?
12%, and 71% of these are due to disorder with significant genetic component
about what percent of families have tried to gather and organize families health histories?
33%
What risk categories do clinicians classify individuals into after this analysis?
Average, moderage, and high risk
What can early identification of individuals at high risk do?
improve, delay, or prevent adverse outcomes in many cases
Can you draw an autosomal dominant pedigree?
Yes
Can you draw and autosomal recessive pedigree?
Yes
Can you draw an x-linked pedigree?
Yes
QOD
Every other day
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every
