REPLI-g amplified DNA enables highly reliable genotyping results
In contrast to these disadvantages, REPLI-g provides highly uniform amplification across the entire genome, with minimal locus bias and minimized mutation rates during amplification (see figures Highly representative amplification and Consistent and accurate whole genome amplification).
Copy number analysis
Gene copy number can vary within individual genomes. Studying gene copy number changes in specific cell types (e.g., tumor cells) has become increasingly important in cancer and cytogenetic research.
Copy number changes are classified as DNA “gains” or “losses” and show characteristic patterns that include mutations at chromosomal and subchromosomal levels. These chromosomal changes are frequently analyzed using comparative genome hybridization (CGH) techniques.
Breakpoint analysis enables the identification of chromosomal regions where “gains” or “losses” of chromosomal fragments have occurred. It also allows the identification of the genes that have been amplified or deleted. The high-quality DNA obtained using multiple displacement amplification (MDA) is more representative of the true genome than other whole genome amplification (WGA) techniques. Research by Hosono et al (2003) (1) and Paez et al (2004) (2) clearly shows that the copy number of different loci is very well preserved after amplification using MDA. In addition, any changes in copy number that are introduced through the process of amplification can be eliminated through normalization of the sample DNA against amplified control DNA.
References
- Hosano, S. et al. (2003) Unbiased whole genome amplification directly from clinical samples. Genome Res. 13, 954.
- Paez, J.G. et al. (2002) A full-coverage, high-resolution human chromosome 22 genomic microarray for clinical and research applications. Hum. Mol. Genet. 11, 3221.