MT2 Flashcards
(99 cards)
How many protein-coding genes in Human Genome Project
19,000
Mutations affecting ___ cells can be inherited (basis of genetic disease)
Mutations affecting ____ cells can result in tumors (usually not inherited/passed along)
Germ
Somatic
Which type of mutation alters reading of RNA
Frameshift mutations
Fragile X syndrome is what type of mutation?
Trinucleotide repeat mutation
Where are polymorphisms usually found?
What are their significance for disease?
NON coding regions (i.e. introns & exons)
They are markers
Copy number variation is an example of a ____, therefore, it’s recognized as a ____
polymorphism
marker
Epigentic change is a ___ that reduces/shuts down ____ by:
polymorphism
translocation (protein synth)
methylation of cytosine residues
Which polymorphism controls gene silencing?
Micro-RNA’s
Autosomal ___ disorder will be evident clinically when only one of the chromosomes in the pair (heterozygous) exhibits a mutation
dominant
Majority of automsomal ____ create outward physical changes.
Early/late age of onset?
Example:
dominant
LATE (even though mutant gene is present from birth)
Huntington’s Disease
If one of the parents is infected and half the offspring are affected, it’s autosomal ____
dominant
Which disease has nearly 100% penetrance
neurofibramotosis
What is variable expressivity?
Trait is seen phenotypically, but is expressed differently among individuals
De novo mutation:
If a kid has an autosomal disorder and neither of the parents have it
Which is a largest group of mendelian disorders?
Autosomal recessive
For autosomal recessive, do the parents usually show the disease?
NO
Autosomal ___ is when you need a germline from both parents to develop disease
recessive
Autosomal recessive commonly effects enzyme for:
metabolism
For autosomal recessive, the age is onset is ___ in life
The expression tends to be ___ uniform and ___ penetrance is common
earlier
more uniform
complete penetrance
X-linked disorders are almost always (dom/rec)
If a man inherits an x-linked recessive (almost all are recessive), is he always affected?
Recessive
YES
When lyonization occurs, what is left in the female zygote?
What is unfavorable lyonization causes clinical evidence of an _____ disease in a ___zygote.
- Example:
Barr body
x-linked disease in a heterozygote.
Ex. hemophilia A
A patient has coarse facial features, clouding of cornea, joint stiffness, and mental retardation. They have _____ which is due to lack of _____. It’s a _______disease
- Mucopolysaccharidoses
- Lack of enzyme to degrade mucopolysachharides
- Lysosomal Storage Disease
What are some things that come from MULTIFACTORIAL inheritance?
Frequency of inheritance:
- Physiologic traits (i.e. height, weight, hair color, BP, etc)
- Common diseases (i.e. diabetes, hypertension, gout, schizo)
-2-7%
Prevalence of newborns that have a chromosomal abnormality:
In as many as __% of 1st trimester spontaneous abortions, the fetus has a chromosomal abnormality
1/200
50%