**1. Introduction**

While the genetic component of Autism Spectrum Disorders (ASD) has been clearly estab‐ lished from various lines of study, the multitude of genes and chromosomal loci associated with ASD has made identification of the underlying molecular mechanisms of pathogenesis difficult to resolve. A range of diverse methodologies and study types have identified both rare and common genetic variants in ASD candidate genes and chromosomal loci. Moreover, the recent development of high-throughput next generation sequencing (NGS) technologies and the increasing usage of chromosomal microarray analysis (CMA) has led to a significant expansion in the number of single nucleotide variants (SNVs) and copy number variants (CNVs) potentially affecting one or more genes that have been identified in ASD individuals. This, in turn, has given critical insight into the molecular and cellular processes that may be preferentially targeted for disruption by genetic lesions in ASD patients.

However, it is important to note that there is no genetic test available for the diagnosis of ASD. Rather, genetic testing is primarily aimed at identifying genetic variants potentially responsi‐ ble for disease pathogenesis in a given individual diagnosed with ASD. Furthermore, the utility of NGS and CMA in genetic evaluation of ASD individuals is dependent on proper interpretation and reporting of test results. In this chapter we will discuss 1) genetic testing technologies currently available for the identification of genetic variation in ASD cases, 2) the genes and genomic loci targeted by single nucleotide and copy number variants that have been linked to ASD susceptibility, 3) the bioinformatics tools that enable researchers to process the enormous amount of genetic data associated with ASD, and 4) challenges that exist in the interpretation and reporting of genetic evaluation results in ASD cases.

© 2013 Larsen et al.; licensee InTech. This is an open access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited. © 2013 The Author(s). Licensee InTech. This chapter is distributed under the terms of the Creative Commons Attribution License http://creativecommons.org/licenses/by/3.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
