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Title: Chimera-free, high copy number YAC libraries and efficient methods of analysis. Final technical progress report

Technical Report ·
DOI:https://doi.org/10.2172/119908· OSTI ID:119908

The first experiment involved a low chimera YAC library in recombination deficient host strains. To determine if the genetic background of the yeast host strain contributes to the formation of chimeric YACs the same YAC ligation mixture was introduced into three isogenic yeast hosts differing only in their recombination abilities. To prepare YACs, human genomic DNA was partially digested with EcoR1 and then ligated to YAC vector pCGS966 arms. DNA was size fractionated before and after ligation by preparative pulsed field gel electrophoresis (CHEF), selecting for fragments greater than 400 kb, and introduced into competent spheroplasts. CHEF gel Southern blots of resulting colony-purified YACs were probed with human DNA to determine if multiple YACs or YAC fragments were present in the same cell. The frequency of chimeric YACs was measured by fluorescence in situ hybridization (FISH) of YACs to human prometaphase spreads. YACs that hybridized to more than one location were assumed to be chimeric. In the second experiment new YAC vectors featuring tags for capture of YACs and YAC inserts were constructed. Yeast Artificial Chromosomes (YACs) have been of tremendous value in the physical mapping of the human genome. Because they can carry very large inserts, YACs are likely not only to contain entire genes but also their control elements. However, the only mode of purification of YAC DNA from current commonly used YAC libraries such as the CEPH library is by pulsed field gel electrophoresis. This is an inefficient, time consuming process and due to the single copy nature of these YACs, often result in poor yields. The vector pCGS1000 was designed to test new efficient ways of YAC DNA purification.

Research Organization:
Collaborative Research, Inc., Bedford, MA (United States)
Sponsoring Organization:
USDOE, Washington, DC (United States)
DOE Contract Number:
FG02-92ER61399
OSTI ID:
119908
Report Number(s):
DOE/ER/61399-T1; ON: DE96001572; TRN: AHC29527%%50
Resource Relation:
Other Information: PBD: [1995]
Country of Publication:
United States
Language:
English