Subtotal amelia in a child with autosomal recessive hypohidrotic ectodermal dysplasia

We report an inbred Tunisian family, in which the proband manifested signs of hypohidrotic ectodermal dysplasia, subtotal amelia, scoliosis and left renal agenesis. Two other family members had the full clinical criteria of hypohidrotic ectodermal dysplasia, characterized by deficient sweat glands, hypodontia, hypoplasia of the mucous glands, and fine hair. Nine family subjects had variable clinical expression of the disorder.     

Sweat testing to identify female carriers of X linked hypohidrotic ectodermal dysplasia.

X linked hypohidrotic ectodermal dysplasia (XHED) affects many epithelial functions, including sweat gland formation. Female carriers who manifest XHED may have defective dentition or a patchy distribution of sweating or both, as determined by starch and iodine sweat testing. Such sweat testing can be useful in assigning carrier status to at risk females in XHED families, and in obtaining an accurate diagnosis for isolated females who present with features of ectodermal dysplasia. The advantages of diagnosing female carriers of XHED include the optimisation of neonatal and paediatric care for affected male infants, who may be at substantial risk of death in infancy.     

先天性外胚层发育不全无汗综合征家系报告及文献复习

目的通过一个家系分析,探讨先天性外胚层发育不全疾病的遗传方式。方法现场对一个无汗先天性外胚层发育不全家系四代27例家庭成员进行调查,并对1例患者进行医学分析。结果患者主要表现为头发稀疏,无牙,无体毛,无汗等症状。家系遗传分析表明该疾病属于X连锁隐性遗传疾病。结论本病发病机制与X染色体上的基因缺陷有关,如ED1、NEMO等,据此可开展进一步基因突变检测。     

A simple technique for recording and counting sweat pores on the dermal ridges

A simple method was devised for recording dermatoglyphics in a form suitable for sweat pore counting. Fifteen members of a family with a hypohidrotic X-linked ectodermal dysplasia made their own hand prints using our method and mailed the results to us for interpretation. The simplicity of the technique also makes it practical to use on new-born males at risk for the condition, or where dermatoglyphic records are required for other purposes. Preliminary data suggest that patchiness of sweat pore distribution on the fingers and palms may be useful in the discrimination of heterozygotes.     

Rapp-Hodgkin hypohidrotic ectodermal dysplasia syndrome

Four members in three generations of a family had Rapp-Hodgkin hypohidrotic ectodermal dysplasia syndrome with variable involvement of teeth, hair, nails and palate, characteristic facies and mild heat tolerance problems. In addition, the proband had a high sweat sodium, hypogenitalism, hypothelia and marked cicatricial scalp atrophy and scarring. Inheritance of the condition was consistent with an autosomal dominant mode and the manifestations are described to delineate further this rare phenotype.     

Prenatal diagnosis of X-linked hypohidrotic ectodermal dysplasia by linkage analysis

Prenatal diagnosis of X-linked hypohidrotic ectodermal dysplasia was previously performed by the direct histological analysis of fetal skin obtained by late second trimester fetoscopy. The recent gene mapping of the locus for the disorder to the region of Xq11-21.1 now permits the indirect prenatal diagnosis of the disorder by the method of linkage analysis, based on closely linked marker loci, during the first trimester of pregnancy. We report the prenatal diagnosis of a male fetus with a high probability of the disorder by a linkage analysis utilizing restriction fragment length polymorphisms at the DXS159, PGK1, and DXS72 loci, from a DNA sample obtained by a chorionic villus biopsy at 9 weeks gestation. After further counseling, the pregnancy was terminated but the diagnosis could not be confirmed by histological analysis, even though analysis of skin samples by light and electron microscopy showed lack of hair germs, primary dermal ridges, and sweat gland primordia, due to the early developmental stage of the fetus. The use of DNA-based linkage analysis now offers the opportunity for an earlier diagnosis of X-linked hypohidrotic ectodermal dysplasia by a method other than fetal skin sampling. However, families must also fully understand the present limitations of the method prior to undertaking the procedure.     

Functional X-chromosomal mosaicism of the skin: Rudolf Happle and the lines of Alfred Blaschko.

In this article, the contribution of Rudolf Happle to the understanding of X-linked skin diseases is reviewed. In 1977 he proposed functional X-chromosomal mosaicism as the genetic mechanism underlying cutaneous anomalies that were seen in a number of X-linked skin diseases such as incontinentia pigmenti or focal dermal hypoplasia. Moreover, he recognized that these cutaneous anomalies followed the lines of Blaschko and thus he could tie in the development of the lines of Blaschko with a datable embryonic event. Convincing proof for the concept of functional X-chromosomal mosaicism was later provided by his group from functional sweat studies in female carriers of the X-linked gene defect hypohidrotic ectodermal dysplasia showing again on the back of the patient a gross, fountain-like mosaic typical of the lines of Blaschko. Moreover, in the years 1977 to 1981 he recognized the mosaic pattern in a syndrome of chondrodysplasia punctata, linear ichthyosis, patchy cicatricial alopecia, unilateral cataracts, and short stature again as a functional X-chromosomal mosaic becoming manifest exclusively in women and proposed that this syndrome, which is today named after him, is because of an X-linked dominant gene defect. Finally, the puzzling molecular genetics of the Happle syndrome are reviewed. Most likely, the Happle syndrome gene is not lethal for hemizygously affected males but rather similar to the example of epilepsy with mental retardation limited to females, the gene actually spares male gene carriers.     

A dental approach to carrier screening in X linked hypohidrotic ectodermal dysplasia.

The frequency of carriers of X linked hypohidrotic ectodermal dysplasia among females with hypodontia of the permanent dentition (excluding third molars) could be as high as 1 in 500, and among females with deciduous hypodontia could be as high as 1 in 50. Since it may be possible to identify carriers form among female hypodontia cases in general by virtue of a reduced sweat pore count, the potential exists for a reasonably practical method of screening for carriers at the population level.     

Functional X-chromosomal mosaicism of the skin: Rudolf Happle and the lines of Alfred Blaschko

In this article, the contribution of Rudolf Happle to the understanding of X-linked skin diseases is reviewed. In 1977 he proposed functional X-chromosomal mosaicism as the genetic mechanism underlying cutaneous anomalies that were seen in a number of X-linked skin diseases such as incontinentia pigmenti or focal dermal hypoplasia. Moreover, he recognized that these cutaneous anomalies followed the lines of Blaschko and thus he could tie in the development of the lines of Blaschko with a datable embryonic event. Convincing proof for the concept of functional X-chromosomal mosaicism was later provided by his group from functional sweat studies in female carriers of the X-linked gene defect hypohidrotic ectodermal dysplasia showing again on the back of the patient a gross, fountain-like mosaic typical of the lines of Blaschko. Moreover, in the years 1977 to 1981 he recognized the mosaic pattern in a syndrome of chondrodysplasia punctata, linear ichthyosis, patchy cicatricial alopecia, unilateral cataracts, and short stature again as a functional X-chromosomal mosaic becoming manifest exclusively in women and proposed that this syndrome, which is today named after him, is because of an X-linked dominant gene defect. Finally, the puzzling molecular genetics of the Happle syndrome are reviewed. Most likely, the Happle syndrome gene is not lethal for hemizygously affected males but rather similar to the example of epilepsy with mental retardation limited to females, the gene actually spares male gene carriers. Am. J. Med. Genet. 85:324–329, 1999. © 1999 Wiley-Liss, Inc.     

Three successive generations of women with anhidrotic/hypohidrotic ectodermal dysplasia

We describe the findings of anhidrotic/hypohidrotic ectodermal dysplasia in three successive generations of a family. All three women had variable alopecia, anhidrosis, hypodontia and malar hypoplasia. Chromosomal studies revealed a defect of the 2q12 region in all three patients. Previous studies have reported rare cases of autosomal dominant ectodermal dysplasia associated with defects in the 2q11-13 region1. These rare disorders are characterized by common anomalies of at least two elements of the ectoderm and its appendages--namely, the skin, teeth, hair, nails and sweat glands. These patients also frequently have chronic dental problems with early loss of teeth and recurrent lung, ear and nose infections secondary to a defect in mucous membrane function. The majority of reported cases of ectodermal dysplasias have historically been X-linked recessive, but our findings indicate that an autosomal version may be more prevalent than previously thought.     

Mutations in WNT10A are frequently involved in oligodontia associated with minor signs of ectodermal dysplasia

Ectodermal dysplasias (ED) are a clinically and genetically heterogeneous group of hereditary disorders that have in common abnormal development of ectodermal derivatives. Hypohidrotic ectodermal dysplasia (HED) is characterized by abnormal development of eccrine sweat glands, hair, and teeth. The X‐linked form of the disease, caused by mutations in the EDA gene, represents the majority of patients with the hypohidrotic form. Autosomal dominant and autosomal recessive forms are occasionally seen, and result from mutations in at least three genes (WNT10A, EDAR, or more rarely EDARADD). We have screened for mutations in EDAR (commonly involved in the hypohidrotic form) and WNT10A (involved in a wide spectrum of ED and in isolated hypodontia) in a cohort of 36 patients referred for EDA molecular screening, which failed to identify any mutation. We identified eight EDAR mutations in five patients (two with homozygous mutations, one with compound heterozygous mutations, and two with heterozygous mutation), four of which were novel variants. We identified 28 WNT10A mutations in 16 patients (5 with homozygous mutations, 7 with compound heterozygous mutations, and 4 with heterozygous mutations), seven of which were novel variants. Our study allows a more precise definition of the phenotypic spectrum associated with EDAR and WNT10A mutations and underlines the importance of the implication of WNT10A among patients with ED. © 2013 Wiley Periodicals, Inc.     

Expression of X-linked hypohidrotic ectodermal dysplasia in six males and in their mothers

Six male patients with confirmed X-linked hypohidrotic ectodermal dysplasia and their mothers were studied to determine the variation of expressivity in patients and heterozygotes, major problems of the patients, and to find a clue to pathogenesis. The number of teeth, conic in shape, in patients varied from none to 14. In addition to hypohidrosis and hypotrichosis, dry skin, reduced salivation, hoarseness and hypoplasia of the nipples were common signs. Five patients had frequent respiratory infections. The mothers lacked more than four permanent teeth, one mother had hypodontia in the deciduous dentition. The sweat pore counts were low in patients, and lower than normal in the mothers. All patients carried beta-hemolytic streptococci, four of them group A either in nose or pharynx, without symptoms. Immunoglobulin values, including IgA were normal in serum and saliva. Unexpectedly, serum parathyroid hormone concentrations both in patients and mothers were low. The major problem of the families was the risk of hyperpyrexia due to hypohidrosis, but the patients' concern was mostly because of their facial appearance.     

Cleavage lines of the skin

Detailed investigation on cleavage lines over the entire area of the body was undertaken in 3 each of male and female cadavers. The directions of cleavage lines showed sex and individual differences. Minute comparison of the diagrams obtained in this study with earlier diagrams revealed the presence of delicate differences in the directions of cleavage lines. Microscopical evaluation of cleavage lines showed that in the regions where cleavage lines were linearly arranged, collagen fibers were regularly arranged in a uniform direction, conforming to the direction of cleavage lines from the shallow reticular layer immediately below the papillary layers to the inner reticular layer where sebaceous and sweat glands existed and that in the regions where cleavage lines were ramified, collagen fibers in these layers lacked directional regularity. The morphology of cleavage lines were considered most influenced by collagen fibers in the epidermal reticular layers from their shallow layers immediately below the papillary layers to the layer where sebaceous and sweat glands existed.     

A novel missense mutation (402C → T) in exon 1 in the EDA gene in a family with X-linked hypohidrotic ectodermal dysplasia

Hypohidrotic ectodermal dysplasia (EDA), or Christ-Siemens-Touraine syndrome, is clinically characterized by hypohidrosis, hypoodontia and hypotrichosis. The X-linked form of the disease has been mapped to Xq12-q13.1, and a gene from this region has recently been cloned. This gene encodes a predicted transmembrane protein of 135 amino acids, which was found to be expressed in keratinocytes, hair follicles, and sweat glands. A variety of rearrangements in this gene have been found in patients with hypohidrotic ectodermal dysplasia.
We have screened the probands from nine unrelated Danish families with hypohidrotic ectodermal dysplasia for mutation in exon 1 of the EDA-gene by polymerase chain reaction-single strand conformation polymorphism (PCR-SSCP). In one large kindred we identified a novel missense mutation (402C → T), which changes a histidine to tyrosine at position 54 in the protein. This mutation cosegregates with the disease in the family and is the first mutation described which affects the predicted transmembrane, hydrophobic domain of the protein.     

Analytical quality of assays and comparison of procedures for the sweat test

Sweat test measuring the chloride ion (Cl(-)) concentration in sweat is a tool for the cystic fibrosis (CF) diagnosis. We evaluated analytical criteria of different available methods and compared them into five hospitals and throught a national quality control program. Sweat tests were performed by stimulation using pilocarpine iontophoresis, sweat collection and measurement of sweat Cl(-) (mmol/L) by titration (colorimetric or coulometric end-point) or by in situ direct potentiometry using a chloride-selective electrode. Indirect determination by sweat conductivity measurement was expressed in mmol/L sodium chloride (NaCl) equivalents (Eq). Linearity range was demonstrated for all measurement procedures in the range 10 to 120 mmol/L. Intra-laboratory coefficients of variation (CVs) were <5% for values between 10 and 100 mmol/L. Inter-laboratory CVs were <3% only for conductivity measurement whatever the range. The comparison of results obtained for a same sweat sample, simultaneously by coulometric and conductivity measurements, demonstrated a first degree linear distribution between 30 to 60 mmol/L Cl(-) allowing us to establish an analytical correspondence table for this range. Thus, calculated values for 30, 40 and 60 mmol/L Cl(-) were respectively 57, 66 and 84 mmol/L NaCl Eq. In conclusion, comparison of methods highlighted that the less the sweat test is automatically controlled, the more the operator influence on results quality is important. Our study supports that sweat test result <50 mmol/L NaCl Eq is unlikely with CF diagnosis in absence of clinical arguments.     

Traf6 is essential for murine tooth cusp morphogenesis.

Ectodermal appendages such as skin, hair, teeth, and sweat glands are affected in patients with hypohidrotic (anhydrotic) ectodermal dysplasia (HED). It has been established that mutations in the tumor necrosis factor (TNF) superfamily of molecules, i.e., ectodysplasin (EDA), EDA receptor (EDAR), and EDAR-associated death domain (EDARADD; the intracellular adaptor for EDAR), are responsible for several forms of HED in humans and mice. We show here by in situ hybridisation that another TNF family (orphan) receptor, TROY (also known TAJ, TAJ-alpha, TRADE, and TNFRSF19), is strongly coexpressed with Edar in the epithelial enamel knot signalling centres that are believe to regulate cuspal morphogenesis during murine tooth development. Traf6 is known to function as an intracellular adaptor protein for Troy and examination of Traf6 mutant mice revealed abnormalities in molar teeth that are similar but more severe than those produced by mutations in Eda signalling molecules. This finding suggests that, in additional to ectodysplasin, another TNF pathway involving Troy/Traf6 is involved in molar tooth cusp formation and identifies an essential role for a Traf in tooth development. Developmental Dynamics 229:131-135, 2004.     

Changes in the index of sweat ion concentration with increasing sweat during passive heat stress in humans

To investigate the pattern changes in the index of sweat ion concentration at skin surface with increasing sweat during passive heat stress in humans, we measured conductivity of the perfused water with sweat as the index of sweat ion concentration and sweat rate, continuously at the chest skin surface. Eight healthy subjects (22.4 ±1.0 years) were passively heated by lower-leg immersion in a hot water bath of 42°C for 50 min in an ambient temperature of 28°C and relative humidity of 50%. The internal temperature (Tor) thresholds of sweat rate and index of sweat ion concentration were almost similar. Concomitant onset for the index of sweat ion concentration and sweat rate occurred but two types of linear regression lines were identified in the relationship between the index of sweat ion concentration and sweat rate at a boundary sweat rate value of 0.30 ± 0.08 mg cm^–2 min^–1. The slope of the regression line at low levels of sweat (slope 0.02 ± 0.01 V mg^–1 cm^–2 min^–1) was significantly gradual compared with that at moderate levels of sweat (slope 0.30 ± 0.08 V mg^–1 cm^–2 min^–1) (P<0.05). These results suggest that at low levels of sweat the index of sweat ion concentration responds gradually with respect to sweat rate, which may be due to the ion reabsorption capacity of the sweat duct, and then the index of sweat ion concentration increased steeply with sweat rate.     

Maspin expression in normal skin and usual cutaneous carcinomas

Maspin is a serine protease inhibitor whose gene is located on 3q27. Several lines of evidence point towards its putative role as tumor suppressor gene and angiogenesis inhibitor; however, there are compelling data showing that maspin is also expressed in the nuclear compartment and might be associated with the differentiation of specific cell lineages. No systematic study of maspin expression in normal skin and usual skin carcinomas have been published so far. We semiquantitatively analyzed the distribution and immunoreactivity pattern of maspin in 14 squamous cell carcinomas (SCCs) and 16 basal cell carcinomas (BCCs) and in the adjacent normal epidermis of all cases. We also examined the correlation of maspin expression with histological type, grade, vascular invasion, perineural infiltration, and mitotic counting. Cytoplasmic expression of maspin was observed in suprabasal, prickle, and granular cell layers of normal epidermis; cells of the germinative hair matrix, Henle's and Huxley's layers, and cuticle of hair follicles; mature sebaceous cells and sweat gland's secretory cells. Nuclear expression was detected in some basal/myoepithelial cells of the sweat glands and scattered mature sebaceous cells. All SCCs but one grade IV SCC showed maspin expression, and it was correlated with the differentiation of these neoplasms. BCCs presented variable maspin expression, while metatypical carcinomas showed moderate to intense maspin expression, nodular BCCs variable contents of maspin and displayed a peculiar distribution, confined to the center of the neoplastic nodules. Two BCCs and one SCC showed maspin nuclear expression. No correlation with other clinical pathological features was observed. Our findings do not support the role of maspin as a tumor suppressor gene and suggest that this serpin is probably associated with specific lines of differentiation.     

参照腋毛范围行腋臭根治术疗效观察

目的观察腋臭大汗腺的分布范围和解剖层次,评估参照腋毛分布范围进行腋臭根治术的疗效。方法回顾分析120例在局部肿胀麻醉下采用沿腋窝皱襞平行切口直视修剪大汗腺治疗腋臭的患者临床资料,了解腋窝顶泌汗腺解剖学特点及手术治疗效果。结果腋窝大汗腺肉眼观察为粉红色粟粒状颗粒,位于真皮层深面,浅部与真皮紧密相连,深部突入脂肪层,与脂肪层连接疏松,局部肿胀麻醉下术中易分离;腋窝大汗腺主要分布在腋毛区域内,腋窝中央皱襞处最密集,超出腋毛范围后大汗腺明显减少,离腋窝中央越远大汗腺越少,大汗腺呈不规则减少趋势,腋毛范围1 cm外已无大汗腺分布。结论参照腋毛分布范围进行腋臭根治术疗效确切,值得临床推广。