The FN1 gene provides instructions for making two types of the fibronectin-1 protein: soluble plasma fibronectin-1 and insoluble cellular fibronectin-1.
At least three mutations in the FN1 gene have been found to cause fibronectin glomerulopathy, a progressive kidney disease that usually begins in adulthood and results in irreversible kidney failure (end-stage renal disease). FN1 gene mutations account for about 40 percent of cases of fibronectin glomerulopathy. One mutation that occurs in multiple families replaces the amino acid tyrosine with the amino acid cysteine at position 973 in the fibronectin-1 protein (written as Tyr973Cys or Y973C; rs137854488).GHR
FN1 mutations have also been found to cause defective fibronectin secretion, leading to spondylometaphyseal dysplasias (SMDs), a diverse group of skeletal dysplasias often manifest as short stature, growth-plate irregularities, and vertebral anomalies, such as scoliosis.10.1016/j.ajhg.2017.09.019