Genetics and Neoplasm Flashcards
What is penetrance?
The % of individuals who will present with the phenotype of a specific genotype
What is an autosomal dominant disorder?
when the offspring receives at least one mutated gene from a parent regardless of sex
When does onset usually occur in a person with an autosomal dominant disorder?
later in life; adulthood
Is a person with an autosomal dominant disorder a carrier?
No
What are examples of autosomal dominant disorders?
Marfan’s syndrome, neurofibromatosis, Huntington disease
T/F. Autosomal dominant disorders usually involve regulatory proteins or key structural components.
True
What is an autosomal recessive disorder?
When the offspring receives affected gene from each parent.
When does onset usually occur in an autosomal recessive disorder?
early in life
How are autosomal recessive disorders different than dominant disorders?
They are far more severe and usually results in loss of function
What are the chances that the offspring will be affected by an autosomal recessive disorder?
1 in 4
How can the child be a carrier but not affected by the autosomal recessive disorder?
if only one parent passes on the mutated “non working” gene
What are the chances that a couple can have a healthy child in an autosomal recessive disorder?
3 in 4
What are the only two ways that a child can be affected by an autosomal recessive disorder?
Both parents have to be affected or carriers
What are examples of autosomal recessive disorders?
Tay Sachs, cystic fibrosis, and PKU
What is X linked recessive inheritance?
abnormalities on the X chromosome.
What are examples of X linked recessive disorders?
Duchenne muscular dystrophy and Hemophilia A and B
What is aneuploidy?
Change in chromosome number
Why do X linked recessive disorders tend to “skip generations”?
A father can give his X affected gene to his daughter but because she has another X gene to compensate she will only be a carrier. If he has a son he will receive the Y unaffected gene so he will not be a carrier nor affected. When the daughter has a son she can give him the X affected gene and he will not have another X gene to compensate therefore will be affected.
What are proto-oncogenes?
normal genes that become cancer causing genes if mutated
What are examples of paraneoplastic syndromes?
SIADH, Cushing’s, Humoral hypercalcemia, Venous thrombosis, and anemia malignancy
What are paraneoplastic syndromes?
Results when tumor markers, unrelated to the tumor site, that are biologically active
What is autocrine stimulation?
The ability for cancer cells to create their own growth factors to self stimulate themselves and continue to replicate
What is angiongenesis?
the development of new blood vessels
What do proto-oncogenes help regulate?
Cell growth and differentiation
