Autism spectrum disorder refers to a broad spectrum of neurodevelopmental disorders characterized by impairments in social interaction and communication that begin at a young age, which commonly exhibits repetitive behaviors and restricted interests (Xiao et al., 2014). This pervasive developmental disorder is more prevalent in males than in females and has recently gained more attention because of its rapid increase in prevalence (Xiao et al., 2014). Today, it is estimated that 69.5 per 10,000 people are on the autism spectrum (Kim, Chae-Seok, & Bong-Kiun, 2016). Autism spectrum disorder is also comorbid with many other disorders including intellectual disabilities (Kim et al., 2016). In a study consisting of 50 toddlers with autism …show more content…
One of these is Rett syndrome, which is an X-linked neurodevelopmental disorder. Children with Rett’s seem to develop normally up unto 6-18 months and then there is regression that is characterized by a loss of motor skills (Percy, 2016). A genetic basis for Rett’s was discovered in 1999 which showed that a mutation in methyl-CpG binding protein 2 (MECP2) was to blame for this disorder (Chahrour & Zoghbi, 2007). In almost 95% of cases mutations in MECP2 are found with most arising from sporadic de novo, or new, mutations. Approximately 70% of all MECP2 mutation are either missense or nonsense, a mutation of nucleotides that leads to premature truncation of the gene by means of a premature stop codon, mutations. Missense mutations are mutations in one nucleotide that in turn affects the codon which then codes for a different amino acid than what is originally supposed to be there. Whereas, nonsense mutations are mutations of nucleotides that leads to premature truncation of the gene by means of a premature stop codon. Missense mutations tend to cause a less severe phenotype then early truncation of the gene. While the genetic factors have now been discovered, there are also neurological factors that come into play. Reduction in the size of the brain and neurons can be seen in most Rett cases. Autopsy’s show that this reduction in brain weight and volume is …show more content…
While these disorders may never fully be understood, advances are still being made in this realm of disorders. In the coming years, it is to be expected that more genetic related studies will help us understand the nature versus nurture link. We may also see more gene regulating developmental process in prefrontal cortex as well as in other brain areas (Xiao et al., 2014). Animal models will also be crucial in this research so that we can easily see the development of certain types of mutations and how they present (Xiao et al.,