Advances in understanding the molecular basis of rare and common disorders, as well as in
the technology of DNA analysis, are rapidly changing the landscape of molecular genetic
and genomic testing. High-resolution molecular cytogenetic analysis can now detect
deletions or duplications of DNA of a few hundred thousand nucleotides, well below the
resolution of the light microscope. Diagnostic testing for “single-gene” disorders can be done
by targeted analysis for specific mutations, by sequencing a specific gene to scan for …