The other technique in diagnostic use is
aCGH. This technique essentially compares the sample genomic DNA with that of a (in our practice sex mismatched) reference, each differentially labeled with a different fluorescent marker, to detect the presence of copy number variations affecting large areas of chromosomes.
Genomic abnormalities in the SCEC tissues were analyzed by Agilent
aCGH G3 Human 4x180k Array.
However, due to its limitations for detecting low-level mosaicism,
aCGH was unable to identify the monosomy 13 cell line.
My opinion is that that all women regardless of age should be offered diagnostic testing and
aCGH because (a) the minimum 1.0% risk of an abnormal CNV by
aCGH is far above the gold standard comparison of 0.5% risk at age 35 years, (b) the yield of abnormalities found is substantially higher by
aCGH than by NIPT, and (c) the risks of an adverse event from diagnostic procedures in experienced hands is much less than often quoted by NIPT companies (1/500 for both CVS and amniocentesis).
Subsequent cytogenetic and array comparative genomic hybridization (
aCGH) studies on MPNST have identified frequent losses on chromosomes 1p, 9p, 11, 12p, 14q, 18, 22q, X, and Y, with focal gains on chromosomes 7, 8q, and 15q [32].
Genome-wide
aCGH analysis on DNA extracted from peripheral blood was carried out using the Nimblegen 135 K WG CGH v.3.1 platform (Figure 1).
Taylor et al., "Genomic profiling of plasmablastic lymphoma using array comparative genomic hybridization (
aCGH): revealing significant overlapping genomic lesions with diffuse large B-cell lymphoma," Journal of Hematology and Oncology, vol.
analyzed 7,753 embryos of 990 women (<35 years, good ovarian reserve) undergoing IVF by an array-based comparative genomic hybridization (
aCGH).
(e) Array comparative genomic hybridization (
aCGH) results showing a ~300 kb hemizygous deletion on X chromosome encompassing the entire coding sequences of the NR0B1 (DAX1) and MAGEB genes.
6p21.2-p12.3 deletion detected by
aCGH in an 8-year-old girl with cleidocranial dysplasia and developmental delay.