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Human vs Nile tilapia LastZ results

Human (Homo sapiens, GRCh38) and Nile tilapia (Oreochromis niloticus, O_niloticus_UMD_NMBU) were aligned using the LastZ alignment algorithm (LastZ) in Ensembl release 99. Human was used as the reference species. After running LastZ, the raw LastZ alignment blocks were chained according to their location in both genomes. During the final netting process, the best sub-chain was chosen in each region on the reference species.

Configuration parameters

ParameterValue
Gap open penalty (O)400
Gap extend penalty (E)30
HSP threshold (K)3000
Threshold for gapped extension (L)3000
Threshold for alignments between gapped alignment blocks (H)2200
Seed and Transition value (T)1
Scoring matrix (Q)
Default:
     A    C    G    T
    91 -114  -31 -123
  -114  100 -125  -31
   -31 -125  100 -114
  -123  -31 -114   91

Chunking parameters

ParameterHumanNile tilapia
Chunk size30,000,00010,100,000
Overlap0100,000
Group set size10,100,000
Masking options

Statistics over 262,797 alignment blocks

Genome coverage (bp) Coding exon coverage (bp)
Human

Uncovered: 3,066,038,233 out of 3,099,750,718
Covered: 33,712,485 out of 3,099,750,718

Uncovered: 17,631,298 out of 38,571,754
Matches: 14,362,660 out of 38,571,754
Mismatches: 6,214,999 out of 38,571,754
Insertions: 362,797 out of 38,571,754
Identity over aligned base-pairs: 68.6%

Nile tilapia

Uncovered: 971,748,084 out of 1,005,681,550
Covered: 33,933,466 out of 1,005,681,550

Uncovered: 26,759,043 out of 51,713,280
Matches: 17,110,857 out of 51,713,280
Mismatches: 7,364,926 out of 51,713,280
Insertions: 478,454 out of 51,713,280
Identity over aligned base-pairs: 68.6%

Block size distribution

Size range All 262,797 alignment blocks Blocks grouped in nets
# blocks Total size (incl. gaps) # nets Total size (incl. gaps)
1 bp - 10 bp
1,697
7.4 kb
10 bp - 100 bp
53,869
4.1 Mb
16,272
1.2 Mb
100 bp - 1 kb
205,509
40.7 Mb
84,312
25.4 Mb
1 kb - 10 kb
1,717
2.6 Mb
9,967
19.6 Mb
10 kb - 100 kb
5
131.0 kb
74
1.2 Mb
100 kb - 1 Mb
1
106.1 kb