Table 4.

Structural Variation and Size Reduction in LTR Retrotransposons

	Families I—XI							**Osr8 and Osr30**
Structure	No. of elements	Remaining size (kb)	Estimated original size (kb)^a	Loss of DNA (kb)	No. of elements^b	Remaining size (kb)	Estimated original size (kb)^a	Loss of DNA (kb)	Primary mechanism
Solo LTRS	348	277	2852	2575	85	115	938	823	Intra-element unequal recombination
Solo LTRs without TSDs	42	37	635	598	9	16	212	196	Inter-element unequal recombination
Intact elements without TSDs	14	103	243	140	2	28	55	27	Inter-element unequal recombination
Truncated elements	358	745	3198	2453	87	272	1021	749	Illegitimate recombination
Intact elements	238	1829	2198	369	33	338	359	21	Illegitimate recombination
Total	1000	2991	9126	6135	216	769	2585	1816

↵a The original size of each element was estimated on the basis of the sizes of full-length and consensus elements identified in each family (Table 1)
↵b A subset of Osr8 and Osr30 were randomly chosen

Analyses of LTR-Retrotransposon Structures Reveal Recent and Rapid Genomic DNA Loss in Rice