Box 4.

Genetic investigations in specific cases

Specific genetic test (Sanger sequencing and copy number analysis) for suspected monogenic disorder

Next-generation sequencing (and copy number analysis) of panel of genes (eg suspected X-linked disorder or based on phenotype, eg epilepsy or neuro-imaging abnormality)

Chromosomal microarray and/or standard karyotype in cultured skin fibroblasts

Methylation tests at imprinted chromosomal loci, including methylation-specific MLPA test for Prader-Willi and Angelman syndromes

Triplet-primed PCR for myotonic dystrophy

Clinical exome sequencing or whole exome sequencing

Whole genome sequencing

MLPA = multiplex ligation-dependent probe amplification; PCR = polymerase chain reaction