SNP Microarray−Pediatric (Reveal®)

Whole blood, DNA, or Labcorp buccal swab kit (buccal swab collection kit contains instructions for the use of a buccal swab)

4 mL or Labcorp buccal swab kit

2 mL (neonatal) (note: this volume does not allow for repeat testing) or two buccal swabs

Green-top (heparin) tube (preferred), yellow-top (ACD) tube or lavender-top (EDTA) tube, DNA in 2 mL tube, Labcorp Genetic buccal swab kit, or Labcorp molecular buccal swab kit

This test will detect chromosomal imbalances that could be associated with developmental delay/congenital anomalies. It provides detection of possible uniparental disomy of any chromosome, the percent and location of homozygosity, including the degree of identity by descent.

This SNP assay does not detect balanced rearrangement, low-level mosaicism (<10%), marker chromosomes that only contain heterochromatin or tetraploidy.

This test was developed and its performance characteristics determined by Labcorp. It has not been cleared or approved by the Food and Drug Administration.

SNP microarray analysis is performed using the Cytoscan® HD Accel platform, which uses 743,130 SNP probes and 2,029,441 NPCN probes with a median spacing of 0.818 kb.

Positive evaluation criteria include: DNA copy gain/loss within known clinically significant gene region of 50 kb or greater. DNA copy number loss >200 kb or gain >500 kb outside known clinically significant regions with at least one OMIM annotated gene or within a region of clear clinical significance. UPD testing is recommended for patient results demonstrating a long contiguous region of homozygosity in a single chromosome >20 Mb interstitially or >10 Mb telomerically (15 and 8 Mb, respectively, for imprinted chromosomes). Contiguous homozygosity >10 Mb within multiple chromosomes suggests common descent. These regions of potential recessive allele risk are designated.