Copy number analysis

One application of such analysis is the detection of chromosomal copy number variation that may cause or may increase risks of various critical disorders.

Array-based methods have been accepted as the most efficient in terms of their resolution and high-throughput nature and the highest coverage (choose an array with over 2 million probes)[3] and they are also referred to as virtual karyotype.

BAC (Bacterial Artificial Chromosome) arrays were historically the first microarray platform to be used for DNA copy number analysis.

Usually, log-ratio measurements are produced by this technology to represent deviation of patient's copy number state from normal.

Such measurements then are studied and those that significantly differ from zero value are announced to represent a part of a chromosome with an anomaly (an abnormal copy number state).

Schematic karyogram of a typical human cell during the G 0 phase in relation to the cell cycle , which is most common phase among human cells, and wherein there will be two pairs of each chromosome (designated 2n), each with one copy of each locus (for a total of 2c). In contrast, at center top it also shows the chromosome 3 pair in metaphase , which is among the phases occurring after DNA synthesis but before cell division , where each chromosome will have two copies of each locus, connected at the centromere , for a total of 2n and 4c.
Further information: Karyotype