Next generation cytogenetics is on its way: Does optical genome mapping turn cytogenetics upside down?

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New research shows that Optical Genome Mapping (OGM) detects abnormalities in chromosomes and DNA very quickly, effectively and accurately. Sometimes even better than all existing techniques together, as they describe in two proof-of-concept studies. This new technique could radically change the existing workflow within cytogenetic laboratories.
Dutch-French research shows that Optical Genome Mapping (OGM) detects abnormalities in chromosomes and DNA very quickly, effectively and accurately. Sometimes even better than all existing techniques together, as they describe in two proof-of-concept studies published in the American Journal of Human Genetics. This new technique could radically change the existing workflow within cytogenetic laboratories.

Human hereditary material is stored in 46 chromosomes (23 pairs). Although those chromosomes are quite stable, changes in number or structure can still occur. A well-known example is Down syndrome, which is caused by an extra chromosome 21 (trisomy 21). An extra chromosome makes a big difference and is quite easy to visualize. But all kinds of other, smaller changes can occur as well in chromosomes. Sometimes pieces of DNA are lost (deletions), sometimes a piece is just repeated (duplication) or it is moved to another place (translocation). An existing piece can also be turned over (inversion) and sometimes new pieces are inserted (insertions). All these structural abnormalities in the chromosomes can cause disease, either congenital genetic diseases, which are present from birth, similar to Down syndrome, or acquired disorders, when the change occurs in a few cells during life which can lead to cancer, such as in leukemia.

Optical Genome Mapping

Cytogenetics is the genetic discipline that examines chromosomes for such abnormalities. To visualize both the large and small changes, several complementary techniques are needed, such as FISH, karyotyping and Copy Number Variant (CNV) microarrays. These are often laborious techniques that individually can only visualize a part of the above-mentioned abnormalities. Recently a new technique has become available -- Optical Genome Mapping -- which more or less brings together the previous techniques. But new techniques must prove themselves in practice. At Radboud University Medical Center (Radboudumc),…
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