The clinical utility of molecular karyotyping using high-resolution array-comparative genomic hybridization

Abstract

Clinical characteristics of patients are not always related to specific syndromes. Array-comparative genomic hybridization (aCGH) is used to detect submicroscopic copy number variants within the genome not visible by conventional karyotyping. The clinical application of aCGH has helped the genetic diagnosis of patients with unexplained developmental delay/intellectual disability, autism spectrum disorders, with or without multiple congenital anomalies. Since 2008, we have implemented aCGH with the 244K and 4×180K Agilent platform on 334 patients with various degrees of developmental delay/intellectual disability, seizures, autism spectrum disorders, multiple congenital anomalies and normal previous conventional karyotype. Many of the patients had also received a variety of other genetic tests (Fragile X syndrome, Rett syndrome, single FISH tests or metabolic screens), which were normal. Clinically significant submicroscopic imbalances with aCGH were detected in 84 (∼25.15%) patients. aCGH is proving to be a powerful tool for the identification of novel chromosomal syndromes, thus allowing accurate prognosis and phenotype–genotype correlations.

Keywords::

• array
• comparative hybridization
• copy number variant
• developmental delay
• genetic diagnosis
• genotype–phenotype
• prenatal diagnosis

Financial & competing interests disclosure

The authors have no relevant affiliations or financial involvement with any organization or entity with a financial interest in or financial conflict with the subject matter or materials discussed in the manuscript. This includes employment, consultancies, honoraria, stock ownership or options, expert testimony, grants or patents received or pending, or royalties.

No writing assistance was utilized in the production of this manuscript.