Thank you very much! It's helpful!
I'm now using IGV to visualize genome of C. elegans. But I found that the same locations shares different GeneBank Accession like his-51 and his-19 gene. And I checked the gtf and bed files downloaded from UCSC, and found that his-51(NM_072895) and his-19(NM_072892) have an completely same location. I'm wondering why?
2 answers
The difference is RNA vs DNA. The histone genes are repetitive. There are four identical copies (plus several nearly identical ones) of this gene in the genome (DNA). The accession numbers you list are RefSeq RNAs for those four copies. So each (identical) RNA maps to multiple loci - and, conversely, each locus indicates multiple mapped RNAs.
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Maybe you are using different assembly releases. make sure they are the same (for example ce11, ce10 ..etc)
Umm, thanks first, and I just downloaded gtf and bed file from UCSC of ce11 version, and his-51, his-19, even his-21 and his-53 have the same location. I didn't make any alignment steps. I'm questioning the gtf(or bed) file itself.
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