Many examples described and theorized in the last 30 years have identified the genetic basis for evolutionary changes such as the modification of the existing toolkit by mutation (in coding or regulatory sequence) or its expansion/constriction by gene duplication and loss [ 1].
The rarity of gene duplication, coupled with the low likelihood of evolving new combinations of transcription factor binding sites before the duplicated gene is nonfunctionalized by random mutations in coding sequences, should therefore make the process of duplication and recruitment of genes encoding physiological or body proteins into the venom gland exceedingly rare.
Several human disorders caused by mutations in genes coding for enzymes dealing with GlcNAc have been identified.
In around 50% of cases, HCM is caused by mutations in genes coding for sarcomere or sarcomere-related genes.
HCM is a myocardial disease characterized by left ventricular hypertrophy, diastolic dysfunction and increased interstitial fibrosis and is mainly caused by mutations in genes coding for sarcomeric proteins.
In addition, dysfunction of mitochondria caused by mutations in genes coding for the organelle components typifies a distinctive class of conditions known as mitochondrial diseases [8].
In up to 50% of cases, hypertrophic cardiomyopathy is caused by mutations in genes coding for sarcomere or sarcomere-related genes, but the often dramatic variation in clinical phenotypes caused by the same or similar mutations remains largely unexplained.
Diseases caused by mutations in genes coding for enzymes and transporters are mostly recessive, while mutations in transcription regulators, structural molecules, nucleic acid binding genes and signal transducers are primarily dominant.
This is different from most other studies showing that anterior segment dysgenesis is mostly caused by mutations in genes coding for transcription factors, such as PAX6, FOXC1, PITX2, PITX3, Foxe3 and Ap2α (2).
Hereditary systemic amyloidoses are autosomal dominant, late-onset disorders caused by mutations in genes coding for a series of plasma proteins, including transthyretin, lysozyme, fibrinogen Aα chain, gelsolin, apolipoprotein A-I (apoA-I) and apoA-II [1].
