A novel mutation in MBTPS2 causes ichthyosis follicularis, alopecia, and photophobia syndrome.

The ichthyosis follicularis, alopecia, and photophobia (IFAP) syndrome is a rare X-linked genodermatosis characterized by noninflammatory spiny follicular hyperkeratosis, severe photophobia, and non-scarring alopecia with variable severities. IFAP syndrome results from mutations in the gene encoding the membrane-bound transcription factor peptidase, site 2 (MBTPS2).We present an 11-year-old male with typical clinical features of IFAP syndrome, including diffuse follicular hyperkeratosis, alopecia, photophobia, psoriasiform plaques, short statue, nail dystrophy, mental retardation, and seizures.A novel missense mutation (NM_015884.4: c.1298T > C; NP_056968.1: p. L433P) in the membrane-bound transcription factor peptidase, site 2 gene (MBTPS2) was identified in our patient. The heterozygous MBTPS2 mutation was identified in his mother but not his father.This study demonstrated a novel MBTPS2 mutation in a patient with IFAP syndrome and thus expands the known MBPTS2 molecular repertoire.