Two Different Mutations in the Same Codon of a Type II Hair Keratin (hHb6) in Patients with Monilethrix

December 1999 in “ Journal of Investigative Dermatology ”

Eve G. Pearce, S. K. Smith, Paul E. Bowden, Sean W. Lanigan

monilethrix hHb6 type II hair keratin point mutations glutamine substitution lysine substitution Taq I restriction site RFLP analysis keratin mutations

Studysummary Mutations in the hHb6 gene cause the hair disorder monilethrix.

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The study examined two unrelated patients with monilethrix, a genetic hair disorder, identifying two novel heterozygous point mutations in the same codon (402) of the hHb6 gene, which encodes a type II hair keratin. In patient A, a G to C transition resulted in a glutamine substitution (E402Q), while in patient B, a G to A transition led to a lysine substitution (E402K). These mutations were absent in unaffected relatives and 10 healthy controls, and disrupted a Taq I restriction site, confirmed via RFLP analysis. The research highlighted the role of hHb6 mutations in monilethrix and provided a diagnostic method for identifying these genetic changes, contributing to the understanding of keratin mutations affecting hair structure integrity.

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Research cited in this study

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research A Mutational Hotspot in the 2B Domain of Human Hair Basic Keratin 6 (hHb6) in Monilethrix Patients

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research Characterization and Chromosomal Localization of Human Hair-Specific Keratin Genes and Comparative Expression During the Hair Growth Cycle

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