Lecture 9 Flashcards
Autosomal recessive inheritance with complete penetrance will affect who?
25% of siblings, males and females equally affected. Typically on affected parent and no affected children of person affected
Autosomal recessive yields which type of pedigree pattern?
horizontal pedigree pattern
Examples of autosomal recessive inheritance
cystic fibrosis, albinism, sickle cell, phenylketonuria
Most common genetic disorder in this country
Cystic Fibrosis
Define cystic fibrosis
autosomal recessive disorder- males and females equally affected
In someone with cystic fibrosis, where is the mutation>
located in chromosome 7- due to mutation in CFTR gene
Most disease is highest incidence in Ireland?
Cystic Fibrosis
What does cystic fibrosis affect?
affects chloride reabsorption, resulting in thick secretions- lungs and pancreas most affected, many are asymptomatic
What will happen to newborns with cystic fibrosis?
Atelectasis- collapsed lung
What happens in the GIT with cystic fibrosis?
meconium ileus, pancreatic enzyme deficiency leading to malabsorption, steatorrhea, bile obstruction– biliary cirrhosis
What may occur just in men with cystic fibrosis?
infertility due to absence of vas deferens resulting in azoospermia
Test done to screen for cystic fibrosis?
Sweat test- chloride level in sweats will be high
What will will be seen on a patient’s fingers who has cystic fibrosis?
clubbing of fingers in chronic lung infection
define albinism
a congenital disorder characterized by the complete or partial absence or defect of an enzyme involved in the production of melanin
Two types of albinism
Oculo cutaneous albinism, ocular albinism
