TABLE 3.

Advantages and limitations of various genetic testing approaches.

Technique	Advantages	Limitations
NGS
Target gene panels	Identifies variants in specific regions (exons and flanking introns) Rapid analysis Customizable Low cost	Variants limited to selected/known genes Cannot identify structural variants Needs frequent updates- time consuming and costly
WES	Identifies variants in all protein-coding regions Lower cost compared to WGS	Cannot detect structural variants or deep intronic variants Requires exome capture or enrichment methods during library preparation
WGS	Identifies variants in the entire genome Detects rearrangements and structural variants, deep intronic variants, CNV	Requires long and complex analysis Expensive Very large volume of data generated
Cytogenetic tests
MLPA	Detects small rearrangements, upto 40 targets High throughput and low cost	Problems with mosaicism Cannot detect heterozygosity
FISH	Detects balanced rearrangement and mosaicism Can quantify multiple copies	Cannot detect small rearrangements Limited number of targets Cannot detect heterozygosity
CGH array	Detects very small rearrangements (100 kb–5 mb) Entire genome can be probed	Cannot detect heterozygosity Low throughput Costly equipment and reagents
Quantitative/Sq- PCR	Detects small rearrangements and point mutations Can quantify multiple copies Low cost	Test optimization and efficiency a concern Limited number of targets