Reconstructing the genomic architecture of mammalian ancestors using multispecies comparative maps

Table 1 Conserved markers, clusters and reversal distances computed with GRIMM-synteny and Multiple Genome Rearrangement Algorithm analysis of comparative gene maps of 470 Type I gene homologues aligned between human (H), mouse (M) and cat (C) genomes.

Distance threshold, G	4	5	6	8	20
No. of markers retained	276	345	379	409	432
% of markers used	59	73	81	87	92
No. of clusters	112	114	106	94	76
d(H, M, C)	222	234	216	201	160
d(A, H) + d(H, H)	19 + 10 = 29	18 + 9 = 27	19 + 10 = 29	15 + 9 = 24	11 + 6 = 17
d(A, C) + d(C, C)	13 + 15 = 28	13 + 11 = 24	13 + 8 = 21	10 + 12 = 22	13 + 5 = 18
d(A, M) + d(M, M)	25 + 41 = 66	31 + 49 = 80	32 + 40 = 72	21 + 43 = 64	24 + 32 = 56
Tree score	123	131	122	110	91

The common ancestor of all three genomes is denoted A, while preancestors for human, mouse and cat are denoted H*, M* and C*, respectively. The total distance between the three genomes, d(H, M, C), is defined as d(H, M) + d(M, C) + d(C, H). The tree score is defined as d(A,H) + d(A,M) + d(A,C)

ISSN: 1479-7364