Horizon is now offering Haplogen’s entire Haploid Gene Trap Mutant Collection to the market.
Retroviral gene trapping
The collection was generated through ‘gene trapping’, a process in which a cassette containing a transcriptional termination sequence (polyadenylation site) is inserted in the human genome by means of a retrovirus.
Integration of the retroviral gene trap into a gene can lead to:
- Insertion into an exon which disrupts the coding sequence and introduces a premature stop codon,
- Insertion into an intron which disrupts splicing, or
- Insertion into an intron which leads to premature transcriptional termination.
This collection, by far the largest such cell line bank available, consists of more than 9,400 mutant clones, affecting more than 3,700 human genes and an additional 1,600 inducible clones covering 1,100 genes. A first release of the collection has recently been published in Nature Methods1 and is in the process of being further expanded.
Western blot analysis of selected KBM7 knockouts.
The antigens recognized by each antibody are indicated on the right.
The collection has been derived from the cell line KBM-72, a human cell line of myeloid origin, which is haploid for all chromosomes except chromosome 8 and a small part of chromosome 15. In these cells, genes have been disrupted by means of a retroviral gene trap3. The KBM-7 cell line has been extensively characterized, and all details are freely available.
Clonal cell lines are provided with “reference clones” that can be used as experimental controls. These clones have a history identical to mutant clones including retroviral transduction, but bear insertions in intergenic regions on (diploid) chromosome 8 and are thus highly unlikely to affect gene function.
1Bürckstümmer T, Banning C, Hainzl P, Schobesberger R, Kerzendorfer C, Pauler FM, Chen D, Them N, Schischlik F, Rebsamen M, Smida M, de la Cruz FF, Lapao A, Liszt M, Eizinger B, Guenzl PM, Blomen VA, Konopka T, Gapp B, Parapatics K, Maier B, Stöckl J, Fischl W, Salic S, Taba R, Knapp S, Bennett KL, Bock C, Colinge J, Kralovics R, Ammerer G, Casari G, Brummelkamp TR, Superti-Furga G and Nijman SMB. A reversible gene trap collection empowers haploid genetics in human cells. Nature Methods. 2013; 10:965–971.
2Kotecki M, Reddy PS, Cochran BH. Isolation and characterization of a near-haploid human cell line. Exp Cell Res. 1999 Nov 1;252(2):273-80.
3Carette JE, Guimaraes CP, Varadarajan M, Park AS, Wuethrich I, Godarova A, Kotecki M, Cochran BH, Spooner E, Ploegh HL, Brummelkamp TR. Haploid genetic screens in human cells identify host factors used by pathogens. Science. 2009 Nov 27;326(5957):1231-5.