title: Genotype analyses of human commensal scalp fungi, Malassezia globosa, and Malassezia restricta on the scalps of patients with dandruff and healthy subjects.
abstract: Dandruff and seborrheic dermatitis are common afflictions of the human scalp caused by commensal scalp fungi belonging to the genus Malassezia. Malassezia globosa and Malassezia restricta are the predominant species found on the scalp. The intergenic spacer regions of these species' rRNA genes contain short sequence repeats (SSR): (GT)n and (CT)n in M. globosa and (CT)n and (AT)n in M. restricta. In the present study, we compared the genotypes (SSR) of M. globosa and M. restricta colonizing the scalps of patients with dandruff and healthy individuals. For M. globosa, the genotype (GT)10:(CT)8 (40.3 %, 25/62) was predominant followed by (GT)9:(CT)8 (14.5 %, 9/62) and (GT)11:(CT)8 (14.5 %, 9/62) in patients with dandruff, whereas the genotypes in healthy subjects were diverse. For M. restricta, the genotype (CT)6:(AT)6 (59.7 %, 37/62) was predominant followed by (CT)6:(AT)8 (24.2 %, 15/62) in patients with dandruff, while four genotypes, (CT)6:(AT)6 (10.5 %, 6/57), (CT)6:(AT)7 (22.8 %, 13/57), (CT)6:(AT)8 (17.5 %, 10/57), and (CT)6:(AT)10 (21.1 %, 12/57), accounted for 71.9 % of all combinations in healthy subjects. The results of this study suggest that the M. globosa genotype (GT)10:(CT)8 and the M. restricta genotype (CT)6:(AT)6 may be involved in the development of dandruff.
authors.affiliation: Department of Dermatology and Allergology, Juntendo University Graduate School of Medicine, 2-1-1 Hongo, Bunkyo-ku, Tokyo, 113-8421, Japan.
authors.forename: Midori
authors.initials: M
authors.lastname: Hiruma
authors.forename: Otomi
authors.initials: O
authors.lastname: Cho
authors.forename: Masataro
authors.initials: M
authors.lastname: Hiruma
authors.forename: Sanae
authors.initials: S
authors.lastname: Kurakado
authors.forename: Takashi
authors.initials: T
authors.lastname: Sugita
authors.forename: Shigaku
authors.initials: S
authors.lastname: Ikeda
mesh_terms: D000328:Adult; D016022:Case-Control Studies; D063807:Dandruff / Q000382:microbiology*; D005260:Female; D005838:Genotype; D064368:Healthy Volunteers; D006801:Humans; D008290:Malassezia / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification*; D008297:Male; D012535:Scalp / Q000382:microbiology*