Autosomal dominant ichthyosis vulgaris

The most common forms of ichthyosis — autosomal dominant ichthyosis vulgaris (IV) and X-linked recessive ichthyosis (XRI) — in many countries occur at frequencies a high as 1/300 and 1/2500, respectively. In fact, the genetic traits for IV and XRI are so frequent that the two diseases sometimes coexist in one and the same family, which may cause confusion as to the inheritance pattern. Although the incidence of IV and XRI is probably similar around the world, climate differences in particular will affect the severity of the disease, and hence its notification by the health care system. 

In the case of ichthyotic scale, obtained from autosomal dominant ichthyosis vulgaris, however, a much more normal gel pattern is obtained (Figure 7.5). The uppermost band, which is absent in psoriatic scale, is clearly present. The lower two bands appear to travel as three. This is probably not significant as this appearance is occasionally given by normal callus extracts and seems to result from technical difficulties in processing dilute solutions. 

Figure 10.3 Comparison of keratohyalin (KH) amount and ultrastructure in autosomal dominant ichthyosis vulgaris (a) and X-linked recessive ichthyosis (b) x31 500...

Refsum s syndrome will only briefly be mentioned here, since our studies together with the dermatologic department of Professor Duperrat and Professor Puissant are reported by Dr. Blanchet-Bardon in more detail (Chapter 9). Though very similar to autosomal dominant ichthyosis vulgaris histopathologically, ichthyosis in Refsum s syndrome may be strictly differentiated from the dominant type by the consistently normal keratohyalin ultra-structure ... 

Structural abnormalities are demonstrable in some dominant types, in keratohyalin (defective in autosomal dominant ichthyosis vulgaris), and tono-filaments (impaired or disturbed in their arrangement in hystrix-like ichthyoses clump formation in bullous ichthyosiform erythroderma or epidermolytic hyperkeratosis shell formation associated with high numbers of binucleate cells in ichthyosis hystrix type Curth-Macklin impairment in ichthyosis hystrix gravior type Rheydt). Keratohyalin and tonofilaments are both structural proteins of keratinizing tissues. 

Feinstein, A., Ackerman, A. B. and Ziprkowski, L. (1970). Histology of autosomal dominant ichthyosis vulgaris and x-linked ichthyosis. Arch. Dermatol, 101,524... 

Anton-Lamprecht, I. and Hofbauer, M. (1972). Ultrastructural distinction of autosomal dominant ichthyosis vulgaris and X-linked recessive ichthyosis. Humangenetik, 15,261... 

Kuokkanen, K. (1969). Ichthyosis vulgaris. A clinical and histopathological study of patients and their close relatives in the autosomal dominant and sex-linked forms of the disease./Icto Dermatol-Venereol (Stockholm), 49 (Suppl. 62), 1... 

Ichthyosis vulgaris is the most common ichthyosis and its onset during childhood is distinctive. The condition is transmitted as an autosomal dominant trait. The trunk and extensor surfaces of the limbs are the site of fine, white and branny scales which may have a pasted on appearance. The flexures are characteristically spared. The face scales only during early childhood. Palms and soles have prominent markings. 

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