ɪn dʒˈænjuːˌɛɹi nˈaɪntiːnhˈʌndɹɪd nˈaɪnti sˈɛvən, ðə hˈɑːloʊdʒnˌoʊm θˈiəɹi wʌz ɛkstˈɛndᵻd, ɪnfˈɔːɹmd baɪ fˈɜːðɚ wˈɜːk ɔnðə məlˈɛkjʊlɚ dʒɪnˈɛɾɪks ʌv ɛntˈɛɹɪk maɪkɹˈoʊbɪəl ɡlˈuːkjʊɹɹˌɑːnaɪd mətˈæbəlˌɪzəm,  tʊ ˈɛmfɐsˌaɪz ðə sˈɛntɹəl ɹˈoʊl ʌv maɪkɹˈoʊbɪəlimˈiːdɪˌeɪɾᵻd hˈoːɹmoʊn mˌɑːdʒuːlˈeɪʃən ˌɛmˌeɪtʃˈɛm æz ɐn ᵻsˈɛnʃəl kəmpˈoʊnənt ʌv mˈʌltaɪsˌɛljʊlˈæɹᵻɾi ænd vˈɜːɾɪbɹˌeɪt baɪˈɑːlədʒi.
In January 1997, the hologenome theory was extended, informed by further work on the molecular genetics of enteric microbial glucuronide metabolism,  to emphasize the central role of microbially-mediated hormone modulation (MHM) as an essential component of multi-cellularity and vertebrate biology.