BIOSC 0150 Lecture Notes - Lecture 31: Fibroblast Growth Factor Receptor 3, Achondroplasia, Dwarfism
Document Summary
Achondroplasia dwarfism is due to decreased bone growth: bones in the arms and the legs tend not to grow as long as they should, a form of dwarfism controlled by one gene with two alleles. o. Cannot be homozygous dominant (aa) because they would be dead. Just because something is dominant, doesn"t mean that it is the most common. Mutations in the fgfr3 gene cause achondroplasia: genes that code for proteins for bone growth. The signal that binds to it is a growth factor. Found on chromosome 4 on the short arm. Fgfr3 signaling normally stops bone growth. o. Turns on a kinase: normally, your bones grow to a certain length then your body sends out the growth factor single the receptor says stop we have gotten to the right length. Fgfr3 amino acid 380 substitution causes receptor activation in the absence of signal: when the signal isn"t there, it is still active.