Genetics Exam 2: Chapter 11 (Childhood Disorders Pt 1)

What is Sickle Cell Disease (SCD)?

a group of inherited red blood cell disorders

What mutation is seen in SCD?

point mutation with a single nucleotide

What is the point mutation in SCD?

the amino acid in the sixth position is VAL instead of GLU

What is the inheritance pattern with SCD?

autosomal-recessive

How is SCD diagnosed?

hemoglobin electrophoresis

What are symptoms of SCD?

poor perfusion, fibrosis, chronic anemia, pain

What are potential triggers for SCD Hypoxemia?

cold environments, dehydration, infections, venous stasis

How is SCD managed?

monitoring organ function, treating infections, supportive care

What is an evolutionary advantage to SCD?

resistance to Malaria

What is Cystic Fibrosis?

It is a genetic disorder of the cell membranes, causes thick, sticky mucus to build up in air passages and pancreas.

What gene is altered in CF?

CFTR

What type of inheritance pattern is seen with CF?

autosomal recessive

How is CF diagnosed?

sweat chloride analysis

What organs are most affected with CF?

lungs and pancreas

How is CF managed?

pulmonary physiotherapy, hydration, lung transplant

What is one evolutionary advantage to CF?

resistance to cholera and typhus

What is Duchenne Muscular Dystrophy (DMD)?

genetic condition that prevents function dystrophin formation after birth

What gene is altered in DMD?

DMD gene

What is the inheritance pattern in DMD?

x-linked recessive

What is the normal function of Dystrophin?

maintains integrity of skeletal muscle and cardiac muscle

What is seen in DMD?

muscles become unstable and break down with every contraction

How is DMD initially diagnosed?

history of progressive muscle weakness and very high blood levels of creatine kinase

What is the confirmatory diagnosis for DMD?

muscle biopsy

Where is muscle weakness first seen in DMD?

neck and hip girdle muscles of young boys

What are symptoms of DMD?

problems walking, decreased lung and pancreas function, heart failure, frequent pneumonia

How is DMD managed?

no cure, steroid therapy, weight management, supportive care

What is classic hemophilia?

hereditary bleeding disorder resulting from deficiency of clotting factors

What gene is altered in classic hemophilia?

F8 gene, which codes for factor VIII clotting factor

What inheritance pattern is seen with classic hemophilia?

x-linked recessive

How is classic hemophilia diagnosed?

F8 gene sequencing, history of bruising and bleeding

How is classic hemophilia managed?

regular infusions of factor VIII, liver transplantation

What is Von Willebrand Disease (VWD)?

A type of hemophilia, deficiency or defect in blood clotting protein

What gene is altered in VWD?

vWF gene

What is the most common inheritance pattern in VWD?

autosomal dominant

What is VWD Type 1?

most common and most mild

What is VWD Type 2?

produces normal amounts of abnormal vWF

What is VWD Type 3?

most rare and most severe, AR inheritance

What are symptoms of VWD Types 1 and 2?

frequent nosebleeds, mouth bleeding, heavy menses, postpartum hemorrhage

How is VWD managed?

regular infusion of factor VII, liver transplant is rare