title: Structural Abnormalities in the Hair of a Patient with a Novel Ribosomopathy.
abstract: We report the biophysical characterization of hair from a patient with a de novo ribosomopathy. The patient was diagnosed with a mutation on gene RPS23, which codes for a protein which comprises part of the 40S subunit of the ribosome. The patient presents with a number of phenotypes, including hypotonia, autism, extra teeth, elastic skin, and thin/brittle hair. We combined optical microscopy, tensile tests, and X-ray diffraction experiments on hair samples obtained from the scalp of the patient to a multi-scale characterization of the hair from macroscopic to molecular length scales and observe distinct differences in the biophysical properties in the patient's hair when compared to hair from other family members. While no differences were observed in the coiled-coil structure of the keratin proteins or the structure of the intermediate filaments, the patient's hair was 22% thinner, while the Young's modulus remained roughly constant. The X-ray diffraction results give evidence that the amount of lipids in the cell membrane complex is reduced by 20%, which well accounts for the other observations. The pathologies characterized by these techniques may be used to inform the diagnosis of similar de novo mutations in the future.
authors.affiliation: Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Richard J
authors.initials: RJ
authors.lastname: Alsop
authors.affiliation: Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Asfia
authors.initials: A
authors.lastname: Soomro
authors.affiliation: Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Yuchen
authors.initials: Y
authors.lastname: Zhang
authors.affiliation: Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Marc
authors.initials: M
authors.lastname: Pieterse
authors.affiliation: Department of Chemistry and Chemical Biology, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Ayodele
authors.initials: A
authors.lastname: Fatona
authors.affiliation: Department of Biology, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Kimberly
authors.initials: K
authors.lastname: Dej
authors.affiliation: Department of Physics and Astronomy, McMaster University, Hamilton, Ontario, Canada.
authors.forename: Maikel C
authors.initials: MC
authors.lastname: Rheinstädter
mesh_terms: D002648:Child; D030342:Genetic Diseases, Inborn / Q000473:pathology*; D006197:Hair / Q000737:chemistry*; D006801:Humans; D008297:Male; D012270:Ribosomes / Q000473:pathology*; D013718:Tensile Strength; D014961:X-Ray Diffraction