Steatocystoma multiplex is associated with the R94C mutation in the KRTl7 gene

Abstract

Steatocystoma multiplex (SM) is an uncommon disorder, characterized by numerous skin-colored subcutaneous cysts. A number of SM pedigrees have been identified with mutations in the keratin 17 (KRT17) gene. The present study examined a four-generation Chinese pedigree with an autosomal dominant mode of inheritance and examined its genetic basis. A review of the literature on KRT17 gene mutations in the SM pedigree was also performed to investigate the KRT17 gene mutation and genotype-phenotype correlation. Exon 1 of the KRTl7 gene was amplified using polymerase chain reaction (PCR) from genomic DNA obtained, which was obtained from 25 family members in the selected Chinese pedigree and from 100 unrelated control individuals. The DNA was then subjected to automatic DNA sequencing. Genealogical investigations demonstrated an autosomal dominant pattern, and direct sequencing of the PCR product revealed a heterozygous mutation, c.280C/T (R94C), which was located in exon 1 of the KRT17 gene in all 10 affected family members. The mutation was not identified in the 15 unaffected family members or in the 100 unrelated control individuals. Therefore, the present study identified a causative mutation in the KRT17 gene in a large Chinese SM pedigree, exhibiting autosomal dominance. A review of the literature suggested that, in addition to the mutation factor, other modifying factors contribute to the phenotype of familial SM.

Follicular occlusion tetrad in a male patient with pachyonychia congenita: clinical and genetic analysis

“…The association of PC with HS has been described without genetic investigations in 5 out of 6 members of a family and that of PC‐1 with HS in a patient in which a heterozygous missense mutation in exon 7 of the KRT 6A gene has been reported . Interestingly, a unique genetic defect has been suggested as the likely explanation for the coexistence of SM and HS in two sisters and subsequent studies have identified KRT17 mutation as a genetic marker for both PC‐2 and familial SM . Mutations of this gene have also been found in HS and pilonidal cyst .…”

“…explanation for the coexistence of SM and HS in two sisters 17 and subsequent studies have identified KRT17 mutation as a genetic marker for both PC-2 and familial SM. 18,23 Mutations of this gene have also been found in HS 24 and pilonidal cyst. 25 In our study, KRT17 mutation was positive in the proband, in his mother and in his maternal grandmother, and specific p.Asn92-Ser mutation was compatible with the diagnosis of PC-2 26 along with typical clinical findings in all patients.…”

Fractionated ablative carbon dioxide laser treatment of steatocystoma multiplex

“…These are often 2–4 mm in diameter, but can grow if unchecked to form 2cm or larger cysts (2). The familial form of SM is associated with a keratin 17 gene mutation (4). Keratin 17 is a type 1 cytokeratin, which is involved in the assembly of intermediate keratin filaments (2).…”

“…The gene for keratin 17 is located on chromosome 17 (2). Recently, a specific causation mutation for this gene on Exon 1 (R94C) has been discovered in a Chinese SM pedigree, and not found in unaffected controls (4). The presence of keratin 17 in sebaceous glands and the increase of sebaceous glands during puberty may explain the average age of onset in SM in early adulthood (5).…”

Diagnosis dan Tatalaksana Steatosistoma

“…Pengobatan klasik adalah dengan memberikan antibiotik golongan tetrasiklin. 4,[23][24][25] Terapi dengan isotretinoin dilaporkan efektif pada beberapa pasien, namun, pada sebagian pasien menyebabkan perburukan kondisi. Telah dilaporkan kekambuhan paska terapi isotretinoin.…”