Genetic Modes Of Inheritance Flashcards
Who do x linked disorder occur most severe in
Males
What type of disorder is duchenne muscular dystrophy? Why type of abnormality is it?
X linked, out of frame deletion so dystrophin is not functional
What type of disorder is Becker muscular dystrophy? Why type of abnormality is it?
X linked, in frame deletion
What is an out of a frame mutation
Deleted message does not fit together
What is an in frame mutation
Deleted message fits together
What type of disorder is hemophilia?
X linked
What happens in hemophilia
Clotting doesn’t happen as it should. Missing factor eight? A missing factor nine? B
What is Becker muscular dystrophy
Allelic form, less severe, occurs later in life
Clinical manifestations of duchenne muscular dystrophy
Passed away from heart and lung complications, need wheelchair by age 13, males show weakness early on, difficulty getting off the floor, calf hypertrophy
What type of disorder is menkes syndrome/ kinky hair syndrome
X linked
Clinical features of menkes syndrome/kinky hair syndrome
Abnormal/sparse kinky hair, hypotonic, seizures, failure to thrive, motor loss, usually die by age 3 but those who survive are disabled
Mike menkes?
Some function of the protein still there so clinical manifestations are not as severe
What happens to males in menkes syndrome/kinky hair syndrome
They do not reproduce
What is haldanes syndrome in kinky hair syndrome?
Affected males do not reproduce but disease incidence stays the same every year. This means that 1/3 of cases each year are new mutations
In what disorder is there a copper transport ATPase error leading to low copper and ceruloplasmin
Menkes disorder
Who is most affected in X-linked recessive disorders where the mother is the carrier
Males because they only have one copy of the X. Daughters can only be carriers
How are daughters affected in excellent recessive disorder’s where the father is affected? Sons?
all daughters are carriers and all sons are unaffected
Is there male to male transmission in X-linked recessive disorders?
No
As is there make to make transmission in x linked dominant disorders
No
Where is there vertical transmission?
X linked dominant disorders
What happens if males are affected in x linked dominant disorders
Males are not affected bc you get a miscarriage
What type of disorder is hypophosphatemic rickets
X linked dominant male lethal
Clinical manifestations of hypophosphatemic rickets
Bowing of lower extremities
Clinical manifestations of aicardi syndrome
agenesis of corpus callosum, distinctive chorioretinal lacunae (lakes in retina)
Type of disorder of aicardi syndrome
X linked dominant male lethal
Clinical manifestations of incontinentia pigmenti
Affects hair skin nails teeth (ectoderm) , seizures, cognitive delay, retinal detachment
Type of disorder of incontinentia pigmenti
X linked dominant male lethal
What disorder has 4 stages
Incontinentia pigmenti
4 stages of incontinentia pigmenti
Blistering
Wart like rashes
Swirling, macular, hyperpigmentation
Lines of lashko, linear hypopigmentation, mimic Christmas tree
Type of disorder of rett syndrome
X linked dominant male lethal
Clinical manifestations of Rett syndrome
Microencephalopathy, regression, seizures, hand wringing
What happens with the transmission in y linked disorders
Male fathers pass to all sons
What are sex limited disorders
Disorders where it will only affect one sex such as breast cancer
What are sex influence disorders
Disorders where both sexes can have the disorder but will express it in different ways such as pattern baldness