From: International Undiagnosed Diseases Programs (UDPs): components and outcomes
Technique | Summary and uses |
---|---|
Chromosomal microarray analysis | Low-cost detection of chromosomal copy-number variation associated with unbalanced chromosomal structural changes |
Gene panel | NGS analysis of one or a small number of genes; selected genes often indicated by clinical features Detection of sequence and structural variants |
Exome sequencing | NGS analysis of the exome. Detection of sequence variants and whole exon deletions, potential to detect structural variants and mosaicism |
Short-read whole genome sequencing | NGS analysis of the whole genome, with read lengths of 100-250bp When compared to exome sequencing, whole genome sequencing has more comprehensive exon coverage, coverage of non-coding regions, and increased sensitivity to detect structural variants Detection of SNVs, small indels, complex structural variants, non-coding splicing or regulatory genomic variants, variants in the mitochondrial genome, and expansion variants |
Long-read whole genome sequencing | NGS analysis of the whole genome, with read lengths of > 10,000bp When compared with short-read sequencing, long-read sequencing has better detection of nucleotide repeat expansions, distinguishing between regions of high homology Accurate detection of structural variants and phase variable genes |
RNA sequencing | NGS and analysis following conversion of RNA to cDNA Detection of abnormal expression and splicing, allele-specific expression, RNA abundance and can aid in interpretation of germline variants |
Methylation profiling | Methylation-specific microarray or sequencing analysis Detection of imprinting defects, mutations in epigenetic regulators |
Metabolomics | Targeted analysis of small-molecule substrates, intermediates, and metabolites Detection of altered biochemical functions |