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W A Griffiths

Publications and source records attributed to W A Griffiths.

At least 19 recordsLinked to original sources

Hay-Wells syndrome is caused by heterozygous missense mutations in the SAM domain of p63.

Hay-Wells syndrome, also known as ankyloblepharon-ectodermal dysplasia-clefting (AEC) syndrome (OMIM 106260), is a rare autosomal dominant disorder characterized by congenital ectodermal dysplasia, including alopecia, scalp infections, dystrophic nails, hypodontia, ankyloblepharon and cleft lip and/or cleft palate. This constellation of clinical signs is unique, but some overlap can be recognized with other ectodermal dysplasia syndromes, for example ectrodactyly--ectodermal dysplasia--cleft lip/palate (EEC; OMIM 604292), limb--mammary syndrome (LMS; OMIM 603543), acro-dermato-ungual-lacrimal-tooth syndrome (ADULT; OMIM 103285) and recessive cleft lip/palate--ectodermal dysplasia (CLPED1; OMIM 225060). We have recently demonstrated that heterozygous mutations in the p63 gene are the major cause of EEC syndrome. Linkage studies suggest that the related LMS and ADULT syndromes are also caused by mutations in the p63 gene. Thus, it appears that p63 gene mutations have highly pleiotropic effects. We have analysed p63 in AEC syndrome patients and identified missense mutations in eight families. All mutations give rise to amino acid substitutions in the sterile alpha motif (SAM) domain, and are predicted to affect protein--protein interactions. In contrast, the vast majority of the mutations found in EEC syndrome are amino acid substitutions in the DNA-binding domain. Thus, a clear genotype--phenotype correlation can be recognized for EEC and AEC syndromes.

Abnormalities, Multiple↗

New mutations in keratin 1 that cause bullous congenital ichthyosiform erythroderma and keratin 2e that cause ichthyosis bullosa of Siemens.

The intermediate filaments of epithelial cells are formed by keratins, a family of structurally related proteins, which are expressed in pairs of acidic (type I) and basic (type II) polypeptides in a tissue- and differentiation-specific manner. Mutations in the genes encoding several keratins have been implicated in the pathogenesis of diseases of keratinization. We report molecular analysis of two patients with the rare autosomal dominant disorders bullous congenital ichthyosiform erythroderma (BCIE) and ichthyosis bullosa of Siemens (IBS). Previous studies have shown that these genodermatoses are due to mutations in the KRT1 and KRT2E genes, respectively. We report a new amino acid substitution mutation in codon 155 of KRT1 (valine to aspartic acid) in the conserved H1 domain of the protein in the patient with BCIE. We also report a novel amino acid substitution mutation in codon 192 of KRT2E (asparagine to lysine) in the conserved 1A helix initiation peptide of the protein in the patient with IBS. Our results demonstrate that these mutations are deleterious to keratin filament network stability and lead to specific clinical inherited disorders of keratinization.

Adult↗

Circumferential fingernail.

We describe a Brazilian girl with a congenital circumferential nail on her left ring finger associated with other bony and soft tissue abnormalities of the affected limb. The tubular nail plate resembling a punch biopsy has been described as a circumferential nail, an extremely rare congenital malformation that can be associated with other congenital anomalies. In our review of the literature, there have only been two previous reports of this unusual condition affecting the fingernails.

Child↗

Netherton's syndrome: increased likelihood of diagnosis by examining eyebrow hairs.

Netherton's syndrome is a rare autosomal recessive condition with variable expression. It comprises an ichthyosiform dermatitis and erythroderma of variable intensity and manifestations, associated with hair abnormalities. The pathognomonic finding (required for diagnosis) is that of trichorrhexis invaginata identified by light and scanning electron microscopic examination of hair shafts. This may be difficult to establish because the hair is sparse and not all hairs exhibit abnormalities. In one patient, cutaneous and hair problems had existed since infancy, and despite repeated examination of scalp hairs, the definitive diagnosis was made only by examining eyebrow hairs at the age of 30 years. We subsequently compared the number of diagnostic lesions found on scalp and eyebrow hairs from two other patients with previously diagnosed Netherton's syndrome. The density of lesions was greater in eyebrow than scalp hair, and furthermore, all eyebrow hairs had at least one lesion. It is proposed that microscopic examination, if possible, of both scalp and eyebrow hair from patients in whom Netherton's syndrome is suspected would increase the chance of a positive diagnosis.

Adult↗

The red face-an overview and delineation of the MARSH syndrome.

The problem of the red face in females is reviewed. After excluding common causes such as contact dermatitis, seborrhoeic eczema and photodermatitis the diseases affecting the remaining patients fall into three groups: marked erythema with no feeling of heat or sensitivity, usually erythromelanosis faciei; marked flushing and burning with intense sensitivity for which the term facial erythrodysaesthesia is proposed; the so-called MARSH syndrome in which an overlap of androgen-dominant symptoms occurs - melasma, acne, rosacea, seborrhoeic eczema, and hirsutism. The latter group may respond best to low dose oral isotretinoin.

Erythema↗

Allelic heterogeneity of dominant and recessive COL7A1 mutations underlying epidermolysis bullosa pruriginosa.

The inherited mechanobullous disease, dystrophic epidermolysis bullosa, is caused by type VII collagen gene (COL7A1) mutations. We studied six unrelated patients with a distinct clinical subtype of this disease, epidermolysis bullosa pruriginosa, characterized by pruritus, excoriated prurigo nodules, and skin fragility. Mutation analysis using polymerase chain reaction amplification of genomic DNA, heteroduplex analysis and direct nucleotide sequencing demonstrated pathogenetic COL7A1 mutations in each case. Four patients had a glycine substitution mutation on one COL7A1 allele (G1791E, G2242R, G2369S, and G2713R), a fifth was a compound heterozygote for a splice site mutation (5532 + 1G-to-A) and a single base pair deletion (7786delG), and a sixth patient was heterozygous for an out-of-frame deletion mutation (6863del16). This study shows that the molecular pathology in patients with the distinctive clinical features of epidermolysis bullosa pruriginosa is heterogeneous and suggests that other factors, in addition to the inherent COL7A1 mutation(s), may be responsible for an epidermolysis bullosa pruriginosa phenotype.

Adolescent↗

The inherited palmoplantar keratodermas.

The inherited palmoplantar keratodermas (PPK) constitute a complex heterogeneous group of genodermatoses, which are difficult to classify clinically. The application of modern molecular biology techniques are leading to an increased understanding of the genetic bases of these disorders and are paving the way towards a classification based upon molecular pathology. We review the recent research advances in this field and the implications for development of novel approaches to disease management.

Humans↗

Multiple endocrine neoplasia type 1 presenting as rosacea.

We present a case of malignant carcinoid initially diagnosed as rosacea. This patient was later found to have an additional functioning parathyroid tumour. Although a pituitary tumour was not identified, the association represents a probable case of multiple endocrine neoplasia type 1 (MEN 1). This autosomal dominant syndrome is characterized by tumours of the pancreas, parathyroid and pituitary. Inoperable carcinoid tumour is best treated with a long-acting somatostatin analogue, octreotide. A diagnosis of MEN 1 has important connotations for the proband's first-degree relatives, who should be entered into an appropriate screening programme.

Aged↗

Keratin 16 and keratin 17 mutations cause pachyonychia congenita.

Pachyonychia congenita (PC) is a group of autosomal dominant disorders characterized by dystrophic nails and other ectodermal aberrations. A gene for Jackson-Lawler PC was recently mapped to the type I keratin cluster on 17q. Here, we show that a heterozygous missense mutation in the helix initiation motif of K17 (Asn92Asp) co-segregates with the disease in this kindred. We also show that Jadassohn-Lewandowsky PC is caused by a heterozygous missense mutation in the helix initiation peptide of K16 (Leu130Pro). The known expression patterns of these keratins in epidermal structures correlates with the specific abnormalities observed in each form of PC.

Amino Acid Sequence↗

Novel mutations in keratin 16 gene underly focal non-epidermolytic palmoplantar keratoderma (NEPPK) in two families.

Keratins K6 and K16 are expressed in suprabasal interfollicular epidermis in wound healing and other pathological conditions associated with hyperproliferation, such as psoriasis and are induced when keratinocytes are cultured in vitro. However, these keratins are also constitutively expressed in normal suprabasal mucosal and palmoplantar keratinocytes. Mutations in keratins have been reported in the basal keratin pair K5 and K14 in epidermolysis bullosa simplex and in suprabasal epidermal keratins K1, K2 and K10 in epidermolytic ichthyoses. Two families with autosomal dominant disorder of focal non epidermolytic palmoplantar keratoderma, have oral mucosal and follicular lesions in addition to the palmoplantar hyperkeratosis. Previous studies have shown linkage in these families to the type I keratin gene cluster at 17q12-q21 and this report shows that the cDNA of affected members of both families have novel heterozygous mutations in the expressed keratin 16 gene. These mutations (R10C and N8S) lie in the helix initiation motif of the 1A domain. These mutations do not appear to cause epidermolysis on light or electron microscopy, which may reflect differences in function, assembly or interaction of the 'hyperproliferative' or 'mucoregenerative' keratins from other major types of keratins. The mutations reported here are the first to describe the molecular pathology of focal non epidermolytic palmoplantar keratoderma.

Base Sequence↗

Reticulate acropigmentation of Dohi.

Two cases of reticulate acropigmentation of Dohi are reported, both patients demonstrating the typical features of this disorder. Reticulate acropigmentation of Dohi (dyschromatosis symmetrica hereditaria or symmetrical dyschromatosis of the extremities) is characterized by pigmented and depigmented macules mixed in a reticulate pattern on the extremities. It was first described in 12 patients from Japan, where it appears to be a well-established condition. Patients have been reported from Europe and a family from India has recently been described. We report two cases of reticulate acropigmentation of Dohi occurring in an Afro-Caribbean and an Indian patient, in order to alert clinicians to the possibility that this disorder may present in the UK.

Adolescent↗

Acquired localized elastolysis associated with varicose veins.

Localized elastolysis refers to a group of heterogeneous conditions which includes cutis laxa. We report a form of localized and non-inflammatory elastolysis evocative of cutis laxa, localized to the anteromedial aspect of the left thigh and knee, acquired at the age of 8 years and associated with unilateral adjacent venous dilatations appearing at the age of 39 years. Our case is clinically and ultrastructurally compatible with cutis laxa. Localized forms of cutis laxa not preceded by inflammation are exceptional; localization on the leg has never been described. This clinical form of elastolysis calls into question the classification of acquired elastolysis. The adjacent varicose veins also raise the question of the risk of subcutaneous damage in this condition.

Adult↗

Ichthyosis bullosa of Siemens--a disease involving keratin 2e.

Ichthyosis bullosa of Siemens (IBS) is a congenital bullous ichthyosis without erythroderma. In contrast to bullous congenital ichthyosiform erythroderma (BCIE), there is a relatively mild involvement of the skin and epidermolytic hyperkeratosis (EHK) is restricted to the upper suprabasal layers of the epidermis. Tonofilament aggregation was observed by EM in suprabasal cells from affected patients in the two families under study, indicative of a keratin abnormality. Keratin 2e is a differentiation specific type II keratin expressed suprabasally in the epidermis. Part of the K2e gene was amplified by polymerase chain reaction using genomic DNA from affected and unaffected individuals from two IBS families. Direct sequencing of polymerase chain reaction products revealed a point mutation in the highly conserved helix termination motif, producing the protein sequence change LLEGEE-LLEGKE. This mutation was found in all affected members of a five-generation kindred and also in a sporadic case in a second unrelated family. No mutation was seen in unaffected individuals. The mutation destroys a MnlI restriction site, which allowed exclusion of the mutation from a population of 50 unaffected unrelated individuals by restriction fragment analysis of K2e PCR products. This is the sixth keratin gene found to be involved in an inherited epidermal disorder.

Base Sequence↗