JOINSOLVER is a web-based software program developed for human immunoglobulin V(D)J recombination analysis, and created by the National Institutes of Health, National Institute of Arthritis and Musculosketelal and Skin Diseases (NIAMS) and the Center for Information Technology (CIT). JOINSOLVER performs immunoglobulin nucleotide and amino acid alignment as well as extensive mutation and CDR3 analysis.

Main Areas of Focus

  • To analyze the CDR3 region of the immunoglobulin genes in human B cells by searching for D germline sequences flanking VH and JH germline genes


  • Web-based software program developed for human immunoglobulin V(D)J recombination analysis
  • Germline databases

Who Can Use This Resource

  • Available for public use.

How To Get Started

JOINSOLVER requires the following sequence criteria for analysis:

  1. The sequence must be from a human immunoglobulin variable region gene (heavy or light chain).
  2. Heavy chain sequence alignments perform best when there are at least four out of five characters in the CTGGG motif from JH germline codons 102-104.
  3. VH segment alignments perform best if codons: 83 to 94 (Kabat numbering), or 95 to 106 (IMGT numbering) are mostly intact.
  4. For the most accurate analysis, the query sequence should not contain ambiguous nucleotides represented by 'X' or 'N'.
Content last reviewed on November 17, 2017