The "New Genetics" in Clinical Practice: A Brief Primer.

Major advances in human genetics have led to the identification of 4451 genes to date with disease-carrying mutations, thereby enabling precise diagnoses of all of these monogenic disorders. Limitations to the use of the "new genetics" do exist, however, including the recognition of genetic heterogeneity, many variants of unknown significance, and incidental diagnoses. This article reviews information to help use these advances to aid accurate diagnoses, identify carriers, and determine prenatal diagnoses, providing opportunities to avoid or prevent serious and fatal genetic disorders.