Krt86, a type II hair keratin gene, encodes a fibrous structural protein. It is crucial in maintaining the structure and integrity of hair. Mutations in Krt86 are associated with monilethrix, an autosomal dominant hair disorder [2,3,4,6,7,8,9]. Additionally, Krt86 is up-regulated in the uterus during implantation, induced by oestradiol, suggesting it might be a marker for non-receptive uterus [5].

Monilethrix is characterized by hair fragility, alopecia, and follicular hyperkeratosis. Multiple studies have identified novel Krt86 mutations in families with monilethrix, expanding the mutational spectrum associated with this disorder [1,2,3,4,6,7,8,9]. For instance, a heterozygous transversion mutation c.1204G > A (p.E402K) in exon 7 of Krt86 was identified in a Chinese Han family with monilethrix [8]. Also, in a Tasmanian family, a novel A280V (c.839C > T substitution) mutation in the coil 2A region of Krt86 was found, causing autosomal dominant monilethrix with incomplete penetrance [9].

In conclusion, Krt86 is essential for hair structure and also plays a role in uterine receptivity during implantation. Research on Krt86 mutations in monilethrix families has enhanced our understanding of the genetic basis of this hair disorder, highlighting the importance of Krt86 in maintaining normal hair function.

References:

1. Li, X-Y, Wang, S, Chen, X-M. 2021. A new KRT86 mutation in a Chinese family with monilethrix. In Clinical and experimental dermatology, 47, 461-463. doi:10.1111/ced.14956. https://pubmed.ncbi.nlm.nih.gov/34610158/

2. van Steensel, Maurice, Vreeburg, Maaike, Urbina, Maria T, Morice-Picard, Fanny, van Geel, Michel. . Novel KRT83 and KRT86 mutations associated with monilethrix. In Experimental dermatology, 24, 222-4. doi:10.1111/exd.12624. https://pubmed.ncbi.nlm.nih.gov/25557232/

3. Redler, S, Pasternack, S M, Wolf, S, Nöthen, M M, Betz, R C. 2015. A novel KRT86 mutation in a Turkish family with monilethrix, and identification of maternal mosaicism. In Clinical and experimental dermatology, 40, 781-5. doi:10.1111/ced.12631. https://pubmed.ncbi.nlm.nih.gov/25809918/

4. Wu, Jin, Lin, Yongli, Xu, Wenrong, Li, Zhongming, Fan, Weixin. . A mutation in the type II hair keratin KRT86 gene in a Han family with monilethrix. In Journal of biomedical research, 25, 49-55. doi:10.1016/S1674-8301(11)60006-7. https://pubmed.ncbi.nlm.nih.gov/23554671/

5. Zhang, He, Zhao, Huashan, Wang, Xi, Cui, Xiaolin, Jin, Lingling. 2020. Keratin 86 is up-regulated in the uterus during implantation, induced by oestradiol. In BMC developmental biology, 20, 3. doi:10.1186/s12861-020-0208-6. https://pubmed.ncbi.nlm.nih.gov/32028879/

6. Deng, Ying, Xia, Dengmei, Wang, Lian, Li, Mengmeng, Li, Wei. 2018. Identification of a novel missense KRT86 mutation in a Chinese family with monilethrix. In The Journal of dermatology, 45, e298-e300. doi:10.1111/1346-8138.14339. https://pubmed.ncbi.nlm.nih.gov/29701253/

7. Dai, Ru, Wang, Tingting, Wu, Xianjie. 2024. Autosomal dominant monilethrix with incomplete penetrance due to a novel KRT86 mutation in a Chinese family. In Anais brasileiros de dermatologia, 99, 606-609. doi:10.1016/j.abd.2022.12.010. https://pubmed.ncbi.nlm.nih.gov/38594178/

8. Ye, Zhen-zhen, Nan, Xu, Zhao, Hong-shan, Chen, Xue-rong, Song, Qing-hua. . Mutation detection of type II hair cortex keratin gene KRT86 in a Chinese Han family with congenital monilethrix. In Chinese medical journal, 126, 3103-6. doi:. https://pubmed.ncbi.nlm.nih.gov/23981620/

9. De Cruz, R, Horev, L, Green, J, Zlotogorski, A, Sinclair, R. . A novel monilethrix mutation in coil 2A of KRT86 causing autosomal dominant monilethrix with incomplete penetrance. In The British journal of dermatology, 166 Suppl 2, 20-6. doi:10.1111/j.1365-2133.2012.10861.x. https://pubmed.ncbi.nlm.nih.gov/22670615/