Mobile elements contribute to the uniqueness of human genome with 15,000 human-specific insertions and 14 Mbp sequence increase

DNA Res. 2018 Oct 1;25(5):521-533. doi: 10.1093/dnares/dsy022.

Abstract

Mobile elements (MEs) collectively contribute to at least 50% of the human genome. Due to their past incremental accumulation and ongoing DNA transposition, MEs serve as a significant source for both inter- and intra-species genetic and phenotypic diversity during primate and human evolution. By making use of the most recent genome sequences for human and many other closely related primates and robust multi-way comparative genomic approach, we identified a total of 14,870 human-specific MEs (HS-MEs) with more than 8,000 being newly identified. Collectively, these HS-MEs contribute to a total of 14.2 Mbp net genome sequence increase. Several new observations were made based on these HS-MEs, including the finding of Y chromosome as a strikingly hot target for HS-MEs and a strong mutual preference for SINE-R/VNTR/Alu (SVAs). Furthermore, ∼8,000 of these HS-MEs were found to locate in the vicinity of ∼4,900 genes, and collectively they contribute to ∼84 kb sequences in the human reference transcriptome in association with over 300 genes, including protein-coding sequences for 40 genes. In conclusion, our results demonstrate that MEs made a significant contribution to the evolution of human genome by participating in gene function in a human-specific fashion.

MeSH terms

  • Animals
  • Chromosome Mapping
  • DNA Transposable Elements*
  • Evolution, Molecular
  • Genome, Human*
  • Genomics* / methods
  • Humans
  • Mutagenesis, Insertional*
  • Nucleotide Motifs
  • Primates / genetics
  • Repetitive Sequences, Nucleic Acid
  • Reproducibility of Results

Substances

  • DNA Transposable Elements