ABSTRACT
Bacterial artificial chromosomes [BACs]-on-Beads [BoBs] is one of the novel and rapid technologies that has been a part of recent advances in genomic technologies. BACs-on- Beads technology [Trade Mark] that assists in speedy detection of copy number changes [CNVs] in targeted genomic regions from minimal amount of DNA. We compared this molecular multiplex, bead-based suspension array that is used in prenatal invasive testing, with conventional cytogenetic and G-banded karyotype techniques. We present the initial BoBs analysis data of 4 patients referred to CABRI with congenital malformations. As per the manufacture's information the targeted region covers at least 4-5 bacs for each region. The selected loci represent the relatively common chromosomal syndromes associated with deletions that can be missed by karyotype analysis. The syndromes are known with definable phenotype and deletion as the major means giving rise to the syndrome. In addition to this the BAC's for the common aneuploidies of chromosomes 13, 18, 21, X, and Y are also present. The method not only detected the known trisomy 21 but also identified a deletion on the long arm of chromosome 7 at q11.2 region that represents the Williams - Beuran Syndrome [WBS] critical region in a patient with suspected trisomy 21. BoBs is potentially a very useful first row test for aneuploidy detection because of its lower cost and rapid detection with minimal amount of DNA especially in newborns with suspected congenital malformations. The results suggest that it is a reliable technique to detect common microdeletions that get missed out by conventional chromosomal analysis