MDM is most common on the Dalmatian island of Mljet (or "Meleda"), thought to be because of a founder effect. It is of autosomal recessive inheritance. It may be caused by a mutation on the "SLURP1" gene, located on chromosome 8.

Meleda disease (MDM) or "mal de Meleda", also called Mljet disease, keratosis palmoplantaris and transgradiens of Siemens, (also known as "Acral keratoderma," "Mutilating palmoplantar keratoderma of the Gamborg-Nielsen type," "Palmoplantar ectodermal dysplasia type VIII", and "Palmoplantar keratoderma of the Norrbotten type") is an extremely rare autosomal recessive congenital skin disorder in which dry, thick patches of skin develop on the soles of the hands and feet, a condition known as palmoplantar hyperkeratosis.

Lelis syndrome it is a genetic disorder, a rare condition with dermatological and dental findings characterized by the association of ectodermal dysplasia (hypotrichosis and hypohidrosis) with acanthosis nigricans. Other clinical features may include palmoplantar hyperkeratosis, nail dystrophy, intellectual deficit, disturbances of skin pigmentation (perioral and periorbital hyperpigmentation, vitiligo, and perinevic leukoderma) and hypodontia. Transmission is autosomal recessive.

Oudtshoorn is a town in Western Cape (formerly Cape Province), South Africa, where KWE ("Oudtshoorn skin") was first described. The disorder is quite prevalent among Afrikaners of South Africa, a population which can be defined as caucasoid native-speakers of Afrikaans, with northwestern European lineage. Among this group, KWE occurs at a rate of approximately 1/7,200.

This relatively high rate of occurrence has been attributed to the founder effect, in which a small, often consanguinous population is formed out of the larger ancestral population, resulting in a loss of genetic diversity. In the context of KWE, the founder effect was confirmed by haplotype analysis, which indicates that the chromosomal origin of a possible genetic mutation responsible for the disorder is particularly common among affected Afrikaners. This is also true in other South Africans of European descent with KWE, and the chromosome of interest in both these and Afrikaner patients strongly points to an unspecified ancestor or ancestral group that may have settled around the Oudtshoorn area.

A second lineage known to exhibit KWE has been reported in Germany, although there it is less prevalent and appears to involve the chromosome from a different ancestral origin than that seen in Afrikaners. KWE has also been noted in other countries around the northwestern region of Europe, such as Denmark.

Roberts syndrome is an extremely rare condition that only affects about 150 reported individuals. Although there have been only about 150 reported cases, the affected group is quite diverse and spread worldwide. Parental consanguinity (parents are closely related) is common with this genetic disorder. The frequency of Roberts syndrome carriers is unknown.

EEM syndrome (or Ectodermal dysplasia, Ectrodactyly and Macular dystrophy syndrome) is an autosomal recessive congenital malformation disorder affecting tissues associated with the ectoderm (skin, hair, nails, teeth), and also the hands, feet and eyes.

KWE is inherited in an autosomal dominant manner. This means that the defective gene responsible for the disorder is located on an autosome (chromosome 8 is an autosome), and one copy of the defective gene is sufficient to cause the disorder when inherited from a parent who also has the disorder.KWE can begin as a spontaneous mutation, first appearing in an individual with no previous family history of the disorder. This may be due to a genetic predisposition for the disorder, possibly connected to the Oudtshoorn ancestral line.

Schöpf–Schulz–Passarge syndrome (also known as "eyelid cysts, palmoplantar keratoderma, hypodontia, and hypotrichosis") is an autosomal recessive condition with diffuse symmetric palmoplantar keratoderma, with the palmoplantar keratoderma and fragility of the nails beginning around age 12. In addition to palmoplantar keratoderma, other symptoms include hypodontia, hypotrichosis, nail dystrophies, and eyelid cysts (apocrine hidrocystomas). Patients may also develop syringofibroadenoma and squamous cell carcinomas.

It was characterized in 1971.

It has been associated with WNT10A.

Nablus mask-like facial syndrome is a microdeletion syndrome triggered by a deletion at chromosome 8 q22.1 that causes a mask-like facial appearance in those affected.

It is characterized by a narrowing of the eyes, tight, glistening facial skin, and a flat, broad nose. Other features of the syndrome include malformed ears, unusual hair patterns on the scalp, bent fingers and toes and joint deformities in the hands and feet, unusual teeth, mild developmental delay, cryptorchidism, and a generally happy disposition. It is a rare genetic disorder by inheritance found in Palestinian people named after Nablus city in the West Bank. It is part of many new genetic disorders of newborns that is increasing exponentially in Arabs in recent years as reported by Centre for Arab Genomic Studies in Dubai.

Bazex–Dupré–Christol syndrome (also known as "Bazex syndrome", and "follicular atrophoderma and basal cell carcinomas") is a very rare condition inherited in an X-linked dominant fashion. Physical findings typically include follicular atrophoderma, multiple basal cell carcinomas, hypotrichosis, and hypohidrosis.

This condition should not be confused with the unrelated condition acrokeratosis paraneoplastica of Bazex, which may also be referred to Bazex syndrome.

Hypotrichosis–lymphedema–telangiectasia syndrome is a congenital syndrome characterized by lymphedema (swelling of tissue due to malformation or malfunction of lymphatics), the presence of telegiectasias (small dilated vessels near the surface of the skin), and hypotrichosis or alopecia (hair loss). Lymphedema usually develops in the lower extremities during puberty. Hair is normal at birth, but usually lost during infancy. Telangiectasias may present on the palms and soles more commonly than on the scalp, legs, and genitalia. The syndrome has been reported in association with both autosomal dominant and autosomal recessive inheritance patterns.

It is associated with a rare mutation of the transcription factor gene "SOX18".

Pure hair-nail type ectodermal dysplasia is a genetic mutation in the "hair matrix and cuticle keratin KRTHB5 gene" that causes ectodermal dysplasia of hair and nail type. Manifestations of this disorder include onychodystrophy and severe hypotrichosis. It represents as an autosomal dominant trait.

Marie Unna hereditary hypotrichosis (also known as "Marie Unna hypotrichosis") is an autosomal dominant condition characterized by scalp hair that is sparse or absent at birth, with variable coarse, wiry hair regrowth in childhood, and potential loss again at puberty.

Unlike other autoinflammatory disorders, patients with CANDLE do not respond to IL-1 inhibition treatment in order to stop the autoinflammatory response altogether. This suggests that the condition also involves IFN dysregulation.

It is estimated to affect less than one in a million people. Only 50 to 100 cases have so far been described.

Hypotrichosis–acro-osteolysis–onychogryphosis–palmoplantar keratoderma–periodontitis syndrome (also known as "HOPP syndrome") is a cutaneous condition characterized by a prominent palmoplantar keratoderma.

A disease that threatens the eyesight and additionally produces a hair anomaly that is apparent to strangers causes harm beyond the physical. It is therefore not surprising that learning the diagnosis is a shock to the patient. This is as true of the affected children as of their parents and relatives. They are confronted with a statement that there are at present no treatment options. They probably have never felt so alone and abandoned in their lives. The question comes to mind, "Why me/my child?" However, there is always hope and especially for affected children, the first priority should be a happy childhood. Too many examinations and doctor appointments take up time and cannot practically solve the problem of a genetic mutation within a few months. It is therefore advisable for parents to treat their child with empathy, but to raise him or her to be independent and self-confident by the teenage years. Openness about the disease and talking with those affected about their experiences, even though its rarity makes it unlikely that others will be personally affected by it, will together assist in managing life.

EEM syndrome is caused by mutations in the "P-cadherin" gene ("CDH3"). Distinct mutations in "CDH3" (located on human chromosome 16) are responsible for the macular dystrophy and spectrum of malformations found in EEM syndrome, due in part to developmental errors caused by the resulting inability of "CDH3" to respond correctly to the "P-cadherin" transcription factor p63.

The gene for p63 ("TP73L", found on human chromosome 3) may also play a role in EEM syndrome. Mutations in this gene are associated with the symptoms of EEM and similar disorders, particularly ectrodactyly.

EEM syndrome is an autosomal recessive disorder, which means the defective gene is located on an autosome, and two copies of the defective gene - one from each parent - are required to inherit the disorder. The parents of an individual with an autosomal recessive disorder both carry one copy of the defective gene, but usually do not experience any signs or symptoms of the disorder.

Acro–dermato–ungual–lacrimal–tooth (ADULT) syndrome is a rare genetic disease. ADULT syndrome is an autosomal dominant form of ectodermal dysplasia, a group of disorders that affects the hair, teeth, nails, sweat glands, and extremities. The syndrome arises from a mutation in the TP63 gene. This disease was previously thought to be a form of ectrodactyly–ectodermal dysplasia–cleft syndrome (EEC), but was classified as a different disease in 1993 by Propping and Zerres.

At this time, there are no other phenotypes (observable expressions of a gene) that have been discovered for mutations in the ESCO2 gene.

The most common known cause of the syndrome are mutations in the Proteasome Subunit, Beta Type, 8 (PSMB8) gene that codes for proteasomes that in turn break down other proteins. This occurs specifically when a mutation causes the homozygous recessive form to emerge. The mutated gene results in proteins not being degraded and oxidative proteins building up in cellular tissues, eventually leading to apoptosis, especially in muscle and fat cells.

A study conducted by Brehm et al. in November 2015 discovered additional mutations that can cause CANDLE syndrome, including PSMA3 (encodes α7), PSMB4 (encodes β7), PSMB9 (encodes β1i), and the proteasome maturation protein (POMP), with 8 mutations in total between them. An additional unknown mutation type in the original PSMB8 gene was also noted.

Wiedemann–Rautenstrauch (WR) syndrome , also known as neonatal progeroid syndrome, is an autosomal recessive progeroid syndrome.

WR was first reported by Rautenstrauch and Snigula in 1977; and the earliest reports made subsequently have been by Wiedemann in 1979, by Devos in 1981, and Rudin in 1988. There have been over 30 cases of WR.

WR is associated with abnormalities in bone maturation, and lipids and hormone metabolism. Affected individuals exhibit intrauterine and postnatal growth retardation, leading to short stature and an aged appearance from birth. They have physical abnormalities including a large head (macrocephaly), sparse hair, prominent scalp veins, inward-folded eyelid (entropion), widened anterior fontanelles, hollow cheeks (malar hypoplasia), general loss of fat tissues under the skin (lipoatrophy), delayed tooth eruption, abnormal hair pattern (hypotrichosis), beaked nose, mild to severe mental retardation and dysmorphism.

Marfan lipodystrophy syndrome (MFLS) has sometimes been confused with Wiedemann–Rautenstrauch syndrome, since the Marfanoid features are progressive and sometimes incomplete. MFLS is caused by mutations near the 3'-terminus of "FBN1" that cause a deficiency of the protein hormone asprosin and progeroid-like symptoms with reduced subcutaneous white adipose tissue.

Hypohidrotic ectodermal dysplasia (also known as "anhidrotic ectodermal dysplasia", and "Christ-Siemens-Touraine syndrome") is one of about 150 types of ectodermal dysplasia in humans. Before birth, these disorders result in the abnormal development of structures including the skin, hair, nails, teeth, and sweat glands.

ADULT syndrome features include ectrodactyly, syndactyly, excessive freckling, lacrimal duct anomalies, dysplastic nails, hypodontia, hypoplastic breasts and nipples, hypotrichosis, hypohidrosis, broad nasal bridge, midfacial hypoplasia, exfoliative dermatitis, and xerosis. The lack of facial clefting and ankyloblepharon are important because they exist in ectrodactyly–ectodermal dysplasia–cleft syndrome (EEC) but not in ADULT syndrome.

BCDS is inherited in an X-linked dominant manner. This means the defective gene responsible for the disorder is located on the X chromosome, and only one copy of the defective gene is sufficient to cause the disorder when inherited from a parent who has the disorder. Males are normally hemizygous for the X chromosome, having only one copy. As a result, X-linked dominant disorders usually show higher expressivity in males than females.

As the X chromosome is one of the sex chromosomes (the other being the Y chromosome), X-linked

inheritance is determined by the gender of the parent carrying a specific gene and can often seem complex. This is because, typically, females have two copies of the X-chromosome, while males have only one copy. The difference between dominant and recessive inheritance patterns also plays a role in determining the chances of a child inheriting an X-linked disorder from their parentage.A locus of Xq24-q27 has been described. However, no gene has been identified.

Genetic testing--x linked dominant pattern associated with various neoplasm (eg. basal cell carcinoma)