2. ACHONDROPLASIA
Literally means “without cartilage formation”
Most common type of dwarfism.
Caused by mutation of gene for (FGFR3)
Average height is about 4 ft.
Short arms and legs.
Large head.
3. Achondroplasia is one of a group of disorders called
chondrodystrophies or osteochondrodysplasias.
May be inherited as an autosomal dominant trait, which means that
if a child gets the defective gene from one parent, the child will have
the disorder.
4. SIGNS AND SYMPTOMS
Abnormal hand appearance with persistent space between the long
and ring fingers
Bowed legs
Decreased muscle tone
Disproportionately large head-to-body size difference
Prominent forehead
5. Shortened arms and legs (especially the upper arm and thigh)
Short stature (significantly below the average height for a person
of the same age and sex)
Spinal stenosis
Spine curvatures called kyphosis and lordosis
6.
7. DENTAL CORRELATION
The administration of thyroid hormone is known to accelerate
dental development and eruption
His dental development is still extremely retarded and is
following a disturbed pattern in which various stages of dental
development are present simultaneously
8. SINGLE GENE
It is considered as single gene because only the Fibroblast Growth
Factor Receptor Gene 3 is affected which is also important in the
maintenance of bone and brain tissues
