Genomic Analysis in Clinical Practice: What are the Challenges?

Targeted genetic testing for certain genetic disorders (for example, chromosomal and monogenic/mendelian conditions) has been routinely offered in clinical settings for several decades. Tests were selected on the basis of signs, symptoms, or a family history of a condition or feature, because this was the most cost-effective way of achieving diagnoses. As the technology to analyze the genetic code has become several 1000-fold cheaper and faster than when such services were introduced, targeted analyses have been replaced by broader ones, notably array comparative genomic hybridization, and whole exome and whole genome analysis. The outputs from these broader technologies require novel bioinformatic approaches to interpret which of the millions of variations routinely detected are disease causing, or, more likely, influence disease predisposition. This chapter discusses some of the implications this shift from focused to broad approaches has for practices of consent and for communication of genetic testing results.