Se estudiaron 31 genes de queratina reportados para ovinos, cabras y humanos entre los cuales tenemos 12 genes del epitelio de tipo I (KRT9, KRT10, KRT12, KRT13, KRT14, KRT15, KRT16, KRT17, KRT18, KRT19, KRT20 y KRT25), 13 genes del epitelio de tipo II (KRT1, KRT2, KRT3, KRT4, KRT5
, KRT6a, KRT6b, KRT6c, KRT7, KRT8, KRT71, KRT79 y KRT80), 3 genes de la fibra de tipo I (KRT31, KRT32 y KRT40) y 3 genes de la fibra de tipo II (KRT81, KRT82 y KRT83) (Zhidong et al.
characterized basal cells by the expression of Trp63, podoplanin (Pdpn or T1a), Ngfr, GsI[beta]4, lectin, and cytokeratin 5 (Krt5
Such tumors express luminal genes at an intermediate level and do not express or express at low levels basal-related genes such as KRT5
. Mutation frequencies are high among HER2-enriched tumors and include mainly TP53 and PIK3CA.
The most common mutation responsible for EBS-MP is a missense mutation, p.pro25leu, in the KRT5
gene (proline to leucine amino acid substitution at the 25th residue of the KRT 5 gene) [77, 84]; however, a mutation in the KRT14 gene and a recently discovered EXPH5 nonsense mutation have also been reported [85-87].
, POFUT1 , and POGLUT1 have been identified to be the causal genes of DDD.[sup] The histopathological change of DDD is very characteristic, showing dilated follicular, fingerlike projections called rete ridges, with thinning of the suprapapillary plates, resulting in an “antler-like” pattern and increased pigmentation of the basal layer.[sup] The histological change of the family 1 in the present study resembled DDD or suggested a coexistence of AI and DDD.
The three major clinical subtypes are all caused by mutations in either the keratin 5 (KRT5
) or keratin 14(KRT14) gene,(2,3)
Among these, Krt5
and Krt14 are known to be coregulated as part of an obligatory acidic/basic heteropolymer expressed in the basal proliferating layer of stratified epithelia.
Citation: Wei Zuo et al.; "p63 Krt5
distal airway stem cells are essential for lung regeneration"; Nature, 2014; DOI: 10.1038/nature 13903
Genomics of Epidermolysis Bullosa EB Type Level of Blistering Genes Simplex Basal cell layer KRT5
, KRT14 Hemidesmosomal Basal cell/lamina BPAG2, ITGB4, ITGA6 lucida interface (PLEC1 with muscular dystrophy) Junctional Lamina lucida LAMA3, LAMB3, LAMC2 Dystrophic Sublamina densa COL7A1 Source: Dr.
Basal cells express the N-terminus-truncated isoform of TRP63 (p63), cytokeratin 5 (KRT5
), nerve growth factor receptor (NGFR), and podoplanin (PDPN) .
(7,8) Recently, the loss-of-function in the keratin 5 (KRT5
) gene and a gene locus mapping to chromosome 17p13.3 have been described in cases of DDD.