Line_s
(long interspersed nuclear elements) Families of long (average length = 6500 bp}, moderately repetitive (about 10,000 copies). LINEs are cDNA copies of functional genes present in the same genome; also known as processed pseudo-genes.

Linkage
The tendency of non-allelic genes to be inherited together more than would be expected if they were assorting independently. Linkage exists between two loci when they are located sufficiently close on the same chromosome that some gametes are produced without crossing-over occurring between the two loci.

Linked genes; linked markers
Genes or markers that show linkage q.v.

Linker
1. A synthetic double-stranded oligonucleotide that carries the sequence for one or more restriction endonuclease sites. 2. A small piece of synthetic double-stranded DNA which contains something useful, such as a restriction site. A linker might be ligated onto the end of another piece of DNA to provide a desired restriction site.

Lipofection
Delivery into eukaryotic .cells of DNA, RNA or other compounds that have been encapsulated in an artificial phospholipid vesicle.