Testing Methods
Our CLIA-certified laboratory provides clinicians with diagnostic genetic testing for a wide variety of disorders. Our testing methods include DNA sequence analysis via next-generation sequencing (NGS) and Sanger sequencing, and DNA copy number variation analysis by chromosomal microarray.
Next-Generation Sequencing (NGS)
NGS is used to sequence our gene panels and for almost all single gene sequencing requests. The coding regions and splice sites are completely sequenced in this test. Sanger sequencing is used to fill in gaps with insufficient coverage for the targeted genes. All clinically significant and novel variants are confirmed by Sanger sequencing as needed.
Sanger Sequencing
Sanger sequencing is used to fully sequence several individual genes. For tests performed by NGS, all clinically significant and novel variants and areas of low coverage will be confirmed by Sanger sequencing as needed.
Sanger sequencing is also used to perform targeted mutation tests offered specifically for the Old Order Amish and Mennonite population and used for known familial mutation (KFM) analysis for variants initially detected in our lab.
Chromosomal Microarray
Whole-genome chromosomal microarray (CMA) is performed using Affymetrix CytoScan HD array platform. This microarray consists of copy number probes and single nucleotide polymorphism (SNP) probes. The copy number probes enable detection of chromosomal aneuploidies and intrachromosomal deletions and duplications. The SNP probe genotyping allows detection of large blocks of homozygosity, which may represent uniparental disomy (UPD), or regions of genome identical by descent (IBD).