Sickle cell anemia is caused by mutations in the HBB gene located on chromosome 11p15.4, which provides instructions for making beta globin. A point mutation in this gene produces hemoglobin S, which replaces normal beta globin and causes red blood cells to take on a sickle shape. The disease follows an autosomal recessive pattern of inheritance, where individuals must inherit two copies of the mutated gene - one from each parent who carries the sickle cell trait - in order to have sickle cell anemia.

1. CAUSES AND INHERITANCE PATTERN
BY JEYASREE M G
B0118066
B.SC. (HONS) BIOMEDICAL SCIENCES

2. 
CAUSES

3. STRUCTURE OF HEMOGLOBIN

5. 
Provides instructions for
making β globin.
Any mutation in the HBB gene
results in production of
abnormal version hemoglobin.
HBB GENE

6. 
HBB GENE
CYTOGENETIC LOCATION: 11p15.4

7. 
A point mutation in HBB gene
produces the variant Hemoglobin S.

8. 
In sickle cell anemia hemoglobin S
replaces both beta-globin subunits in
hemoglobin

9. 
Autosomal recessive pattern.
The parents carrying sickle cell trait are
healthy.
The children having sickle cell anemia
inherited the sickle traits from both the
parents.
Male and female are equally affected.
25% recurrence chance.
INHERITANCE PATTERN