include incontinentia pigmenti, focal dermal hypoplasia and so on. X-linked recessive inheritance The last kind is X-linked recessive inheritance, in this kind of inheritance, patients can be of any sex and the prevalence in men is higher than that in women. Male patients cannot pass the disease on to their sons. Cases of skin disease that may be inherited in this kind of mode include fabry disease, anhidrotic ectodermal dysplasia, dyskeratosis congenita and so on. Multiple gene (polygenic) Multiple-gene inheritance of genodermatosis refers to the inheritance of a skin disease caused by multiple genetic abnormalities. Cases of skin disease that may be inherited in this mode include vitiligo, psoriasis, pemphigus vulgaris, systemic lupus erythematosus and so on. Chromosome Chromosome inheritance of genodermatosis refers to the inheritance of a skin disease caused by chromosome abnormality. The same disease can be inherited in different modes. For instance, epidermolysis bullosa can be inherited in the mode of autosomal dominant or in the mode of autosomal recessive. Types Genodermatosis has many types, many of which are rare. Common types Ichthyosis Ichthyosis refers mainly to ichthyosis vulgaris, a common genodermatosis, people with this disease have a fishy, dry skin, which usually appears in early childhood and may disappear in adulthood. The prevalence of ichthyosis vulgaris is high, affecting almost 1 per 250 people. There are also rare types of ichthyosis, such as epidermolytic hyperkeratosis, harlequin ichthyosis and so on. Rare types Michelin tyre baby syndrome Michelin tyre baby syndrome is a rare genodermatosis that occurs at birth, the skin of the patients is stacked symmetrically in layers like the image of the Michelin tyre's mascot, which is also how this disease got its name. Epidermolysis bullosa Epidermolysis bullosa is a rare type of genodermatosis, people with this disease have blisters on their skin and this disease is never completely cured for a lifetime. Epidermolysis bullosa is mainly subdivided into four types: dystrophic epidermolysis bullosa, epidermolysis bullosa simplex, junctional epidermolysis bullosa and kindler syndrome. Almost 1 in 50,000 people has epidermolysis bullosa. Pachyonychia congenita Pachyonychia congenita is a rare type of genodermatosis, its clinical manifestations are abnormal enlargement of fingernails or toenails, excessive or poor palmoplantar keratinization, excessive sweating in the palmar or the plantar. Between 5000 and 10000 people in the world have pachyonychia congenita. Epidermolytic palmoplantar keratoderma Epidermolytic palmoplantar keratoderma often appears at birth and it is almost impossible to be cured completely. The