Cloning and characterization of three human forkhead genes that comprise an FKHR-like gene subfamily

Genomics. 1998 Jan 15;47(2):187-99. doi: 10.1006/geno.1997.5122.


Alveolar rhabdomyosarcomas are associated with unique chromosomal translocations t(2;13) and t(1;13), which arise from fusion of the genes for the paired box proteins PAX3 and PAX7, respectively, to the FKHR (forkhead in rhabdomyosarcoma) gene on chromosome 13q14. Here we report the identification and characterization of three novel human forkhead genes with similarity to FKHR. The three genes (HGMW-approved symbols FKHRP1, FKHRL1, and FKHRL1P1) map to chromosomal regions 5q35.2-q35.3, 6q21, and 17p11, respectively. Based on amino acid sequence comparisons of their forkhead domains, FKHRL1, FKHRL1P1, and FKHRP1 share 86, 84, and 68% identity, respectively, with FKHR. While FKHR and FKHRL1 are expressed in every human adult tissue examined, FKHRP1 mRNA expression could not be detected, and FKHRL1P1 expression was present only at low levels. FKHR and FKHRL1 share a similar genomic organization, each having a very large intron 1 (FKHR approximately 130 kb and FKHRL1 > 90 kb), which bisects their respective forkhead domains at identical positions, as well as a second intron just downstream of each stop codon. FKHRP1 and FKHRL1P1 lack introns and contain stop codons that prevent them from yielding full-length proteins. Thus, while FKHR and FKHRL1 represent functional genes, FKHRP1 and FKHRL1P1 probably are processed pseudogenes. These results suggest that these four genes represent an FKHR-like gene subfamily within the larger human forkhead gene family.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Base Sequence
  • Blood Proteins / genetics
  • Cell Cycle Proteins
  • Cell Line
  • Chromosome Mapping
  • Cloning, Molecular*
  • DNA, Complementary / isolation & purification
  • DNA-Binding Proteins / biosynthesis
  • DNA-Binding Proteins / chemistry*
  • DNA-Binding Proteins / genetics*
  • Forkhead Box Protein O1
  • Forkhead Box Protein O3
  • Forkhead Transcription Factors
  • Humans
  • In Situ Hybridization, Fluorescence
  • Molecular Sequence Data
  • Multigene Family*
  • Organ Specificity / genetics
  • Protein Structure, Tertiary
  • Rhabdomyosarcoma, Alveolar
  • Sequence Homology, Amino Acid
  • Transcription Factors / biosynthesis
  • Transcription Factors / chemistry*
  • Transcription Factors / genetics*


  • Blood Proteins
  • Cell Cycle Proteins
  • DNA, Complementary
  • DNA-Binding Proteins
  • FOXO1 protein, human
  • FOXO3 protein, human
  • FOXO4 protein, human
  • Forkhead Box Protein O1
  • Forkhead Box Protein O3
  • Forkhead Transcription Factors
  • Transcription Factors

Associated data

  • GENBANK/AF032885
  • GENBANK/AF032886
  • GENBANK/AF032887
  • GENBANK/AF032888