PEDIGREE ANALYSIS Flashcards
show a record of the family of an
individua
Pedigree charts
They can be used to study the transmission of a
hereditary condition
PEDIGREE CHART
Aimed at determining the type of inheritance
pattern that a gene follows
PEDIGREE CHART
They are particularly useful when there are large
families and a good family record over several
generation
PEDIGREE CHART
Indicated by a solid horizontal
straight line connecting 2
individuals
o Married couple/Mating
Children
Indicated by a solid horizontal
that is connected to the
mating/married
_________s depicted as square and _________ as circle.
male and female
– unknown gender; it does not mean that
he/she is a transgender
Diamond
are identified by Roman numerals
GENERATIONS
numbered from the left
Arabic numerals
Person who is the focus of the pedigree
o The one who is being interviewed
PROBAND
- Indicated by an arrow and the letter P
PROBAND
Dominant type of trait would manifest even if it
would only appear on one allele.
AUTOSOMAL DOMINANT INHERITANCE
VARIOUS TYPES OF INHERITANCE
- Autosomal Dominant Inheritance
- Autosomal Recessive Inheritance
- Sex-linked Dominant Inheritance – Very Rare
- Sex-linked Recessive Inheritance – Very Rare
AUTOSOMAL DOMINANT INHERITANCE example
Polydactyly
o Huntington disease
o Neurofibromatosis
o Polycystic kidney disease
Recessive needs 2 alleles for the disease to
manifest
AUTOSOMAL RECESSIVE INHERITANCE
Autosomal recessive inheritance is a common
mode of transmission for genetic disorders,
particularly those that involve defective enzymes
AUTOSOMAL RECESSIVE INHERITANCE
The disease only manifests if it is in homozygous
condition
AUTOSOMAL RECESSIVE INHERITANCE
AUTOSOMAL RECESSIVE INHERITANCE Example
The deviation between the observed and expected out-
comes
random sampling error.
