Sjögren–Larsson syndrome (SLS) is an autosomal recessive form of ichthyosis apparent at birth.

Sjögren–Larsson syndrome is a rare autosomal, recessive, neurocutaneous disease. This disease can be identified by a triad of medical disorders. The first is ichthyosis, which is a buildup of skin to form a scale-like covering that causes dry skin and other problems. The second identifier is spastic paraplegia which is characterized by leg spasms. The final identifier is intellectual delay.

The gene of SLS is found on chromosome 17. In order for a child to receive SLS both parents must be carriers of the SLS gene. If they are carriers their child has a ¼ chance of getting the disease. In 1957 Sjogren and Larsson proposed that the Swedes with the disease all descended from a common ancestor 600 years ago. Today only 30–40 persons in Sweden have this disease.

CHILD syndrome is a rare disorder with only 60 recorded cases worldwide thus far in literature.

It is associated with a deficiency of the enzyme "fatty aldehyde dehydrogenase". At least 11 distinct mutations have been identified.

CHILD syndrome is not fatal unless there are problems with the internal organs. The most common causes of early death in people with the syndrome are cardiovascular malformations. However, central nervous system, skeletal, kidney, lung, and other visceral defects also contribute significantly.

There are many types of ichthyoses and an exact diagnosis may be difficult. Types of ichthyoses are classified by their appearance and their genetic cause. Ichthyosis caused by the same gene can vary considerably in severity and symptoms. Some ichthyoses do not appear to fit exactly into any one type. Different genes can produce ichthyoses with similar symptoms. Of note, X-linked ichthyosis is associated with Kallmann syndrome (close to "KAL1" gene). The most common or well-known types are as follows:

Congenital Ichthyosiform Erythroderma (CIE), also known as Nonbullous congenital ichthyosiform erythroderma is a rare type the ichthyosis family of skin diseases which occurs in 1 in 200,000 to 300,000 births.

Treatment with isotretinoin may induce substantial resolution of skin lesions, but the risk of secondary infection remains.

Ichthyosis is a family of rare genetic skin disorders characterized by dry, thickened, scaly skin.

There are more than 20 types of ichthyosis which range in severity of symptoms, outward appearance, underlying genetic cause, and mode of inheritance (e.g., whether the abnormal gene inherited is dominant, recessive, autosomal, or X-linked). Ichthyosis comes from the , since dry, scaly skin is the defining feature of all forms of ichthyosis.

The severity of symptoms can vary enormously, from the mildest, most common, type such as ichthyosis vulgaris which may be mistaken for normal dry skin up to life-threatening conditions such as harlequin type ichthyosis. Ichthyosis vulgaris accounts for more than 95% of cases.

Most cases are X-linked recessive but there may be as many as three types. As well as a classical X-linked form, there is another type where females are partially affected and another where females have full IFAP symptoms. The gene or genes causing this disease are not known.

Trichothiodystrophy (TTD) is an autosomal recessive inherited disorder characterised by brittle hair and intellectual impairment. The word breaks down into "tricho" – "hair", "thio" – "sulphur", and "dystrophy" – "wasting away" or literally "bad nourishment". TTD is associated with a range of symptoms connected with organs of the ectoderm and neuroectoderm. TTD may be subclassified into four syndromes: Approximately half of all patients with trichothiodystrophy have photosensitivity, which divides the classification into syndromes with or without photosensitivity; BIDS and PBIDS, and IBIDS and PIBIDS. Modern covering usage is TTD-P (photosensitive), and TTD.

Ichthyosis hystrix is a group of rare skin disorders in the ichthyosis family of skin disorders characterized by massive hyperkeratosis with an appearance like spiny scales. This term is also used to refer to a type of epidermal nevi with extensive bilateral distribution.

An extremely rare disease of which only a few isolated cases are known.

IFAP syndrome is an extremely rare genetic syndrome. It is also known as Ichthyosis follicularis, alopecia, and photophobia syndrome or simply ichthyosis follicularis. It is extremely rare: there were only 10 known cases (all male) in 1998.

Hystrix-like ichthyosis–deafness syndrome (also known as "HID syndrome") is a cutaneous condition characterized by a keratoderma.

Tetra-amelia syndrome has been reported in only a few families worldwide.

According to a 2011 study by Bermejo-Sanchez, amelia – that is, the lacking of one or more limbs – occurs in roughly 1 out of every 71,000 pregnancies.

Aside from the skin scaling, XLI is not typically associated with other major medical problems. Corneal opacities may be present but do not affect vision. Cryptorchidism is reported in some individuals. Some individuals can also be seen to have an intellectual disability, this is thought to be due to deletions encompassing neighboring genes in addition to "STS".

Female carriers generally do not experience any of these problems but rarely can have difficulty during childbirth, as the STS expressed in the placenta plays a role in normal labor. For this reason carriers should ensure their obstetrician is aware of the condition.

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.

Sabinas brittle hair syndrome, also called Sabinas syndrome or brittle hair-mental deficit syndrome, is an autosomal recessive congenital disorder affecting the integumentary system.

CIE has symptoms very similar to Lamellar ichthyosis (LI) but milder and is considered by many scientists to be a variant of that disease, so both diseases are grouped under the title autosomal recessive congenital ichthyosis (ARCI).

The baby is often born in a collodion membrane, a shiny, wax outer layer on the skin and usually with ectropion, having the lower eyelid turned outwards. When the membrane is shed the skin is red with a generalized white scale. Palms, soles and areas on the joints are often affected with hyperkeratosis, a thickening of the layer of dead skin cells on the surface of the skin. In classical CIE (unlike LI) there is little eclabion (eversion of the lips), ectropion and alopecia (hair loss).

Many people with ACRI don't fit neatly into the definition of LI or CIE but have characteristics of both diseases. The definitions of CIE and LI describe the extremes of the range of ACRI.

Rothmund–Thomson syndrome (RTS), also known as poikiloderma atrophicans with cataract or poikiloderma congenitale, is a rare autosomal recessive skin condition originally described by August von Rothmund (1830–1906) in 1868. Matthew Sydney Thomson (1894–1969) published further descriptions in 1936.

There have been several reported cases associated with osteosarcoma. A hereditary genetic basis, mutations in the DNA Helicase "RECQL4" gene, causing problems during initiation of DNA replication has been implicated in the syndrome

There have been 30 cases of Marden-Walker Syndrome reported since 1966. The first case of this was in 1966 a female infant was diagnosed with blepharophimosis, joint contractures, arachnodactyly and growth development delay. She ended up passing at 3 months due to pneumonia.

Senter syndrome (also known as "Desmons' syndrome") is a cutaneous condition characterized by similar skin changes and congenital hearing impairment to keratitis–ichthyosis–deafness syndrome, but is associated with glycogen storage leading to hepatomegaly, hepatic cirrhosis, growth failure and mental retardation.

Sabinas brittle hair syndrome is inherited as an autosomal recessive genetic trait.

In a study by Howell et al. patients were located and studied by means of complete histories and physical examinations, analyses of serum trace metals, ceruloplasmin concentration, urine and serum amino acids, and routine metabolic urine screens. In addition, serum and urine luteinizing hormone (LH) and follicle-stimulating hormone (FSH) values were determined, and were interpreted in conjunction with total plasma estrogen, estradiol, and testosterone levels. Close examination demonstrated the scalp hairs were very brittle, coarse, wiry in texture, and broke off quite easily with mechanical trauma such as combing and brushing. Some hairs could be visualized in their follicles, which were broken off at the skin line. Most patients had accompanying hyperkeratosis (thickening of the skin) of moderate degree on exposed surfaces. Maxillary hypoplasia (midfacial retrusion) was significant in many patients. The brittle, short hair, reduced eyelashes, crowded teeth, and dull appearance created a characteristic facial appearance. Post-pubertal patients had development of secondary sexual characteristics consistent with their age, except for sparse pubic escutcheons. All cases studied demonstrated some degree of mental deficiency; I.Q.'s ranged between 50–60. A deficiency in eye–hand coordination was also noted.

Features of TTD can include photosensitivity, icthyosis, brittle hair and nails, intellectual impairment, decreased fertility and short stature. The acronyms PIBIDS, IBIDS, BIDS and PBIDS give the initials of the words involved. BIDS syndrome, also called Amish brittle hair brain syndrome and hair-brain syndrome, is an autosomal recessive inherited disease. It is nonphotosensitive. BIDS is characterized by brittle hair, intellectual impairment, decreased fertility, and short stature. There is a photosensitive syndrome, PBIDS.

BIDS is associated with the gene MPLKIP (TTDN1).

IBIDS syndrome, following the acronym from ichthyosis, brittle hair and nails, intellectual impairment and short stature, is the Tay syndrome or sulfur-deficient brittle hair syndrome, first described by Tay in 1971. (Chong Hai Tay was the Singaporean doctor who was the first doctor in South East Asia to have a disease named after him). Tay syndrome should not be confused with the Tay-Sachs disease. It is an autosomal recessive congenital disease. In some cases, it can be diagnosed prenatally. IBIDS syndrome is nonphotosensitive.

The photosensitive form is referred to as PIBIDS, and is associated with ERCC2 and ERCC3.

Frequencies of this disease are the greatest in Norway with a few Finnish cases have also having been noted to date. Some cases have been found in other ethnicities such as in people of Indian or Japanese descent as well as a north Italian family. These cases are scattered and there are potentially more under reported cases as this disease is often under diagnosed for other cutaneous diseases. It is most prevalent in a defined region in the middle of Norway and Sweden with a heterozygote carrier frequency of 1 in 50.