Molecular Technologies and Test Issues

Molecular genetic testing has been around since the discovery and offering of clinical testing for the first gene sequenced. However, in recent years the methods and scope of molecular genetic testing have evolved significantly to encompass next-generation sequencing, multigene panels, and whole exome and genome testing. With this evolution in molecular methods, the nomenclature and variant evaluation and annotation processes are crucial for the systematic and standard interpretation of molecular test results. This chapter will provide the laboratory genetic counselor with information about the common sample types analyzed by molecular techniques for the purposes of genetic testing and the various methodologies available and their limitations. Guidelines are given for the standard approach to molecular variant reporting with respect to nomenclature and variant classification.