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Human vs Chimpanzee LastZ results

Human (Homo sapiens, GRCh38) and Chimpanzee (Pan troglodytes, Pan_tro_3.0) were aligned using the LastZ alignment algorithm (LastZ) in Ensembl release 91. 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)5000
Threshold for gapped extension (L)5000
Threshold for alignments between gapped alignment blocks (H)3000
Masking count (M)10
Seed and Transition value (T)1
Scoring matrix (Q)
Primate:
    A    C    G    T
   90 -330 -236 -356
 -330  100 -318 -236
 -236 -318  100 -330
 -356 -236 -330   90

Chunking parameters

ParameterHumanChimpanzee
Chunk size30,000,00010,100,000
Overlap0100,000
Group set size10,100,000
Masking options{default_soft_masking => 1}{default_soft_masking => 1}

Statistics over 189,136 alignment blocks

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

Uncovered: 266,973,690 out of 3,099,750,718
Covered: 2,832,777,028 out of 3,099,750,718

Uncovered: 107,978 out of 38,571,754
Matches: 38,050,582 out of 38,571,754
Mismatches: 376,019 out of 38,571,754
Insertions: 37,175 out of 38,571,754
Identity over aligned base-pairs: 98.9%

Chimpanzee

Uncovered: 472,997,174 out of 3,231,170,666
Covered: 2,758,173,492 out of 3,231,170,666

Uncovered: 1,995,954 out of 37,531,681
Matches: 35,199,257 out of 37,531,681
Mismatches: 317,497 out of 37,531,681
Insertions: 18,973 out of 37,531,681
Identity over aligned base-pairs: 99.1%

Block size distribution

Size range All 189,136 alignment blocks Blocks grouped in nets
# blocks Total size (incl. gaps) # nets Total size (incl. gaps)
1 bp - 10 bp
1,953
10.5 kb
10 bp - 100 bp
20,384
1.0 Mb
5,296
293.5 kb
100 bp - 1 kb
38,133
15.5 Mb
11,435
4.1 Mb
1 kb - 10 kb
56,952
246.5 Mb
6,354
20.7 Mb
10 kb - 100 kb
68,459
2.2 Gb
1,627
50.7 Mb
100 kb - 1 Mb
3,255
431.8 Mb
429
102.3 Mb
1 Mb - 10 Mb
17
44.5 Mb
10 Mb - 100 Mb
18
883.9 Mb
100 Mb - 1 Gb
13
1.8 Gb