Monilethrix is a rare hereditary disorder of hair first described by Walter G. Smith in 1879, and usually transmitted as autosomal dominant trait. It is characterized hy bead like enlargement af the affected hair, alapecia resulting from ha.ir breakage and keratosis pila.l is. This 3 year old female child patient has been suffered from easy destrurtion of beaded scalp hair and follicular hyperkeratosis of the occipital region since infancy. Past hiatory was ncecontributory and the pe,digree of family showed autosomal dominant trait. Physical examinatior was not rernarkable except skin lesian and laboratory findings were within normal limit. Microscopic finding of the affected hair showed alternating constrictians and node. The scalp bivpsy findings showed mild hyperkeratosis, keratotic plug, mild cellular infiltration of papillary derrnia and perifollicular area.
Child ; Child, Preschool ; Female ; Hair ; Humans ; Keratosis ; Monilethrix* ; Scalp ; Skin

Monilethrix is a rare hereditary disorder of hair which was described by smith in 1879. The scalp hair is most frequently affected but the body or sexual hair are rarely affected. The affected hair shows periodic constrictions that break easily, so the hair could not grow more than a few millimetere long. It is thought that the node of the affected hair is normal and the thin internodal segment is deficient in hair matrix. Keratosis pilaris is generally an associated feature. We experienced a case of monilethrix with keratosis pilaris. The 4 years old male patient with monilethrix affected only scalp hair with keratosis. The family history was non-contributory.
Child, Preschool ; Constriction ; Hair ; Humans ; Keratosis* ; Male ; Monilethrix* ; Scalp

Monilethrix is a rare familiar disorder of unknown cause, occurring in either sex, and ueually confined to the scalp. In most cases it is manifested in early childhood. lt is characterized by localized or widespread dystrophy of hair and follicles, the shafts showing regular variations in diameter producing alternate "nodes" and "internodes" which confer a striking beaded or moniliform appearance on the hair. We experienced a case of monilethrix, which was associated with keratosis pilaris and occurred in three generations. The patient's one sibling, mother, 4 uncles and 2 aunts of mother side and grandmother with her sister were all affected with a similar diaorder of hair.
Family Characteristics ; Hair ; Humans ; Keratosis ; Monilethrix* ; Mothers ; Scalp ; Siblings ; Strikes, Employee

BACKGROUNDMonilethrix is an autosomal dominant hair disorder characterized clinically by alopecia and follicular papules. In this study, we collected a Han monilethrix family to detect the mutations in patients and investigated the correlation between the genotype and phenotype of monilethrix.

METHODSIn this study, we identified a Chinese family with monilethrix through light microscopic and scanning electron microscopic (SEM) examination. Genomic DNA from peripheral blood samples was prepared. DNA samples from controls and monilethrix patients were subject to polymerase chain reaction (PCR) amplification. Two pairs of primers were used to amplify the seventh exon of KRT86. Mutation screening of the PCR products was detected using direct sequencing.

RESULTSLight microscopic examination showed a regular alternate enlargement and narrow area. SEM examination showed that part of the cuticle of the nodules shed and disappeared gradually in the narrow area with granular protrusions on the surface similar to the erosion-like structure. Parallel longitudinal ridge and groovepattern appeared, and the ridges varied in width, like dead wood. A heterozygous transversion mutation c.1204G > A (p.E402K) in the seventh exon of KRT86 was identified in both patients.

CONCLUSIONSThe mutation of extron 7 of KRT86 identified plays a major role in the pathogenesis of this pedigree with monilethrix, and is a mutation hot spot of KRT86. Further research is needed to explore the relationship between the phenotype and the mutation of the type II hair keratin gene KRT86 of monilethrix.

Asian Continental Ancestry Group ; genetics ; China ; ethnology ; Humans ; Keratins, Hair-Specific ; genetics ; Keratins, Type II ; genetics ; Microscopy, Electrochemical, Scanning ; Monilethrix ; etiology ; genetics ; pathology ; Mutation