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kil·o·base (kb),

Unit used in designating the length of a nucleic acid sequence; 1 kb equals a sequence of 1000 purine or pyrimidine bases.
Farlex Partner Medical Dictionary © Farlex 2012


A unit of measurement of the length of a DNA or RNA sequence equal to 1000 base pairs of DNA or 1000 bases of RNA.
Collins Dictionary of Medicine © Robert M. Youngson 2004, 2005

kilobase (kb)

1000 BASES of DNA or RNA, used as a unit of length of single-stranded molecules. The kilobase is often also used as the unit of length for double-stranded molecules, though these should more correctly be measured in kilobase pairs (kbp).
Collins Dictionary of Biology, 3rd ed. © W. G. Hale, V. A. Saunders, J. P. Margham 2005
References in periodicals archive ?
Lower right: fragments per kilobase of transcript per million mapped reads (FPKM) of PSMC3IP.
Abbreviations: Bta-RHO, bovine rhodopsin; EL, extracellular loop; FPKM, fragments per kilobase of exon per million fragments mapped; GO, gene ontology; GPCR, G-protein-coupled receptor; Gr, gustatory receptor; KEGG, Kyoto Encyclopedia of Genes and Genomes; mRNA, messenger RNA; TM, transmembrane helix; Tpa-OPNGq1, Todarodes pacificus, rhodopsin.
Gene counts were normalized to the values of Reads Per Kilobase of transcript per Million mapped reads (RPKM).
Following deep sequencing, expression levels of mapped genes were calculated and normalized by reads per kilobase transcriptome per million mapped reads (RPKM) to eliminate the influence of gene lengths and sequencing discrepancy.
The lncRNA and mRNA sequence reads of the IDD and control groups were normalized to fragments per kilobase of transcript per million mapped reads (FPKM) values [29].
Gene expression level analysis was performed by the reads per kilobase per million mapped reads (RPKM) method using the formula RPKM = 103C/NL, where C is the number of mappable reads that uniquely align to a unigene, N is the total number of mappable reads that uniquely align to all unigenes, and L is the sum of the unigenes in base pairs (Mortazavi et al., 2008).
Expresion diferencial de genes.--El siguiente paso en el analisis de RNA-Seq fue la reconstruccion del transcriptoma y su cuantificacion El nivel de expresion de todos los transcriptos que mapearon en el genoma fue cuantificado como fragmentos por kilobase de exon por millon de reads (FPKM).
For each of the RefSeq genes, reads uniquely aligned within the genome-mapped exons of that gene were summed and then divided by the sum of the exon lengths to yield reads per kilobase. The resulting modified raw gene count was then divided by the total number of uniquely aligned reads for the sample, yielding reads per kilobase per million uniquely mapped reads (RPKM) (15).
All breaks in MLL occur within the same 8 kilobase (kb) region, (bcr) and create in-frame fusion mRNAs and fusion proteins with the translocation partner gene.
These results provide direct evidence that asbestos fibers induced kilobase pair deletion mutations in a transgenic mouse mutation system, and that these were mediated by oxyradicals.
These genome-wide technologies use in situ hybridization for SNP detection and contain anywhere from 1,000 to 500,000 SNP markers, with about one marker per five kilobase, or 5 kb.