Symptoms include:

- Severe sunburn when exposed to only small amounts of sunlight. These often occur during a child's first exposure to sunlight.

- Development of many freckles at an early age

- Rough-surfaced growths (solar keratoses), and skin cancers

- Eyes that are painfully sensitive to the sun and may easily become irritated, bloodshot and clouded

- Blistering or freckling on minimum sun exposure

- Spider Veins

- Limited growth of hair on chest and legs

- Scaly skin

- Dry skin

- Irregular dark spots on the skin

- Corneal ulcerations

All types of Griscelli syndrome have distinctive skin and hair coloring.

Type 1 is associated with eurological abnormalities. These include delayed development, intellectual disability, seizures, hypotonia and eye abnormalities.

Type 2 - unlike type 1 - is not associated primary neurological disease but is associated with an uncontrolled T lymphocyte expansion and macrophage activation syndrome. It is often associated with the hemophagocytic syndrome. This latter condition may be fatal in the absence of bone marrow transplantation.

Persons with type 3 have the typical light skin and hair coloring but are otherwise normal.

Tricho-hepato-enteric syndrome is one particular form of intractable diarrhea of infancy, presenting typically in the first month of life. These babies were usually born small for their age and continue to experience failure to thrive, usually with a final short stature. Typical facial features include prominent forehead and cheeks, a broad nasal root and widely spaced eyes (hypertelorism). Their hairs are woolly, easily removed and poorly pigmented. Liver disease is mainly present as cirrhosis or fibrosis, and staining might reveal high iron content of the liver cells (consistent with hemochromatosis). Most evaluated patients had some degree of decrease in intelligence.

When symptoms occur, they can include acute attacks (similar to acute intermittent porphyria), skin damage, or both. Acute attacks usually begin in adulthood and cause abdominal pain, vomiting, diarrhoea and constipation. During an attack, a person may also experience muscle weakness, seizures, and mental changes such as anxiety and hallucinations. These signs and symptoms are triggered by nongenetic factors such as certain drugs, dieting or fasting, certain hormones and stress.

Some people with variegate porphyria have skin that is overly sensitive to sunlight (photosensitive). Areas of skin exposed to the sun develop severe blistering, scarring, changes in pigmentation, and increased hair growth. Exposed skin becomes fragile and is easily damaged.

Rarely, the signs and symptoms of variegate porphyria can begin in infancy or early childhood. In such cases, the signs and symptoms are usually more severe than those starting later in life. In addition to the health problems described above, children with this disorder may have mental retardation and grow more slowly than other children.

Xeroderma pigmentosum (XP) is a rare autosomal recessive genetic disorder of DNA repair in which the ability to repair damage caused by ultraviolet (UV) light is deficient. In extreme cases, "all" exposure to sunlight must be forbidden, no matter how small; as such, individuals with the disease are often colloquially referred to as "Moon children". Multiple basal cell carcinomas (basaliomas) and other skin malignancies frequently occur at a young age in those with XP; metastatic malignant melanoma and squamous cell carcinoma are the two most common causes of death in XP victims. This disease is present in both genders and in all races, with an incidence of 1:250,000 in the United States. XP is roughly six times more common in Japanese people than in other groups.

Normally, damage to DNA in epidermal cells occurs during exposure to UV light. The absorption of the high-energy light leads to the formation of pyrimidine dimers, namely cyclobutane-pyrimidine dimers and pyrimidine-6-4-pyrimidone photoproducts. In a healthy, normal human being, the damage is first excised by endonucleases. DNA polymerase then repairs the missing sequence, and ligase "seals" the transaction. This process is known as nucleotide excision repair.

Symptoms include brittle hair, mild mental retardation and nail dysplasia. The syndrome was first observed in Sabinas, a small community in northern Mexico.

The principal biochemical features of the illness are reduced hair cystine levels, increased copper/zinc ratio, and presence of arginosuccinic acid in the blood and urine.

The key finding is brittle hair with low sulfur content, but alternating dark and light bands under polarizing microscopy, trichoschisis, and absent or defective cuticle are additional important clues for the diagnosis of trichothiodystrophy. Review of literature reveals extensive associated findings in trichothiodystrophy. Amino acid analyses of control hair when compared with those of patients with the Sabinas syndrome showed very striking differences with regard to content of sulphur amino acids. As in previous descriptions of amino acid abnormalities in the trichorrhexis nodosa of arginosuccinicaciduria, there were increases in lysine, aspartic acid, alanine, leucine, isoleucine, and tyrosine.

Trichothiodystrophy represents a central pathologic feature of a specific hair dysplasia associated with several disorders in organs derived from ectoderm and neuroectoderm. Trichothiodystrophy or TTD is a heterogeneous group of autosomal recessive disorders, characterized by abnormally sulfur deficient brittle hair and accompanied by ichthyosis and other manifestations.

Patients with trichothiodystrophy should have a thorough evaluation for other associated manifestations, including investigation of photosensitivity and DNA repair defects. Because the disease appears to be inherited in an autosomal recessive pattern, detection of low-sulfur brittle hair syndrome is also important for genetic counseling.

Griscelli syndrome type 2 (also known as "partial albinism with immunodeficiency") is a rare autosomal recessive syndrome characterized by variable pigmentary dilution, hair with silvery metallic sheen, frequent pyogenic infections, neutropenia, and thrombocytopenia.

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

Variegate porphyria, also known by several other names, is an autosomal dominant porphyria that can have acute (severe but usually not long-lasting) symptoms along with symptoms that affect the skin. The disorder results from low levels of the enzyme responsible for the seventh step in heme production. Heme is a vital molecule for all of the body's organs. It is a component of hemoglobin, the molecule that carries oxygen in the blood.

Tricho-hepato-enteric syndrome (THE), also known as syndromic or phenotypic diarrhea, is an extremely rare congenital bowel disorder which manifests itself as intractable diarrhea in infants with intrauterine growth retardation, hair and facial abnormalities. Many also have liver disease and abnormalities of the immune system. The associated malabsorption leads to malnutrition and failure to thrive.

It is thought to be a genetic disorder with an autosomal recessive inheritance pattern, although responsible genes have not been found and the exact cause remains unknown. Prognosis is poor; many patients die before the age of 5 (mainly from infections or cirrhosis), although most patients nowadays survive with intravenous feeding (parenteral nutrition).

SBCADD is included as a secondary target condition in most newborn screening programs, as the key analyte is the same as is used to identify isovaleric acidemia. Most cases have been Hmong individuals, who are asymptomatic. There are isolated case reports where individuals have been identified with SBCADD in addition to developmental delay and epilepsy. It is currently unclear what the complete clinical presentation of SBCADD looks like. There is some concern that these cases with additional symptoms may reflect an ascertainment bias rather than being a true representation of the clinical spectrum of the disease. Currently, there is no accepted treatment, as most affected individuals do not require any. Some recommend avoidance of valproic acid, as it can be a substrate for 2-methylbutyryl-CoA dehydrogenase.

In medicine, the term collodion baby applies to newborns who appear to have an extra layer of skin (known as a "collodion membrane") that has a collodion-like quality. It is a descriptive term, not a specific diagnosis or disorder (as such, it is a syndrome).

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.

2-hydroxyglutaric aciduria is an organic aciduria, and because of the stereoisomeric property of 2-hydroxyglutarate different variants of this disorder are distinguished:

The signs/symptoms of this condition are consistent with the following:

- Intellectual disability,

- Muscular hypotonia

- Encephalitis

- Seizures

- Aphasia

Affected babies are born in a collodion membrane, a shiny, waxy-appearing outer layer to the skin. This is shed 10–14 days after birth, revealing the main symptom of the disease, extensive scaling of the skin caused by hyperkeratosis.

With increasing age, the scaling tends to be concentrated around joints in areas such as the groin, the armpits, the inside of the elbow and the neck. The scales often tile the skin and may resemble fish scales.

Infants born with this condition have very short arms and legs, a narrow chest, and a prominent, rounded abdomen. This disorder is also characterized by an opening in the roof of the mouth (cleft palate), distinctive facial features, an inward- and downward-turning foot (clubfoot), and unusually positioned thumbs (hitchhiker thumbs).

The signs and symptoms of atelosteogenesis, type 2, are similar to those of another skeletal disorder called diastrophic dysplasia. Atelosteogenesis, type 2 tends to be more severe, however.

2-Methylbutyryl-CoA dehydrogenase deficiency, also called 2-Methylbutyryl glycinuria or short/branched-chain acyl-CoA dehydrogenase deficiency (SBCADD), is an autosomal recessive metabolic disorder. It causes the body to be unable to process the amino acid isoleucine properly. Initial case reports identified individuals with developmental delay and epilepsy, however most cases identified through newborn screening have been asymptomatic.

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.

Glutaric acidemia type 2 often appears in infancy as a sudden metabolic crisis, in which acidosis and low blood sugar (hypoglycemia) cause weakness, behavior changes, and vomiting. There may also be enlargement of the liver, heart failure, and a characteristic odor resembling that of sweaty feet. Some infants with glutaric acidemia type 2 have birth defects, including multiple fluid-filled growths in the kidneys (polycystic kidneys). Glutaric acidemia type 2 is a very rare disorder. Its precise incidence is unknown. It has been reported in several different ethnic groups.

Atelosteogenesis, type II is a severe disorder of cartilage and bone development. It is rare, and infants with the disorder are usually stillborn; however, those who survive birth die soon after

Glutaric acidemia type 2 is an autosomal recessive metabolic disorder that is characterised by defects in the ability of the body to use proteins and fats for energy. Incompletely processed proteins and fats can build up, leading to a dangerous chemical imbalance called acidosis.

Symptoms for Alström syndrome generally appear during infancy with great variability in age. Some of the symptoms include:

- Heart failure (Dilated cardiomyopathy) in over 60% of cases, usually within the first few weeks after birth, but sometimes the onset is in adolescence or adulthood.

- Light sensitivity and vision problems (Cone-rod dystrophy) in all cases, usually within 15 months of birth and progressively worsening until about 20 years of age

- Delays in early, developmental milestones in 50% of cases, learning disabilities in about 30% of cases

- Obesity in 100% of cases, apparent by 5 years of age, but often apparent in infancy (Alström infants usually have normal birth weights, and by adolescence, weights tend to be in the high-normal to normal range)

- Nystagmus (usually affects the children) one of the first symptoms to occur which causes involuntary rapid eye movement.

- Heart failure (Dilated cardiomyopathy) in over 60% of cases, usually within the first few weeks after birth, but sometimes the onset is in adolescence or adulthood.(chronic)

- Mild to moderate bilateral sensorineural hearing loss.

- Type 2 diabetes usually occurs in early childhood.

- Hyperinsulinemia/ insulin resistance—development of high level of insulin in blood.

- Steatosis (fatty liver) and elevated transaminases (liver enzymes) often develop in childhood and can progress in some patients to cirrhosis and liver failure.

- Endocrine dysfunctions may occur where the patient may experience an under or over active thyroid gland, weak growth hormone, increased androgen in females, and low testosterone in males.

- Slowly progressive kidney failure can occur in the second to fourth decade of life.

A DNA repair-deficiency disorder is a medical condition due to reduced functionality of DNA repair.

DNA repair defects can cause an accelerated aging disease or an increased risk of cancer, or sometimes both.

Alström syndrome, also called Alstrom-Halgren syndrome, is a rare genetic disorder caused by mutations in the gene ALMS1. It is among the rarest genetic disorders in the world, as currently it has only 266 reported cases in medical literature and over 501 known cases in 47 countries. It was first described by Carl-Henry Alström in Sweden in 1959. Alstrom syndrome is sometimes confused with Bardet-Biedl syndrome, which has similar symptoms. Bardet-Biedl syndrome tends to have later onset in its symptoms. The likelihood of two carrier parents both passing the gene and therefore having a child affected by the syndrome is 25% with each pregnancy. The likelihood of having a child who is only a carrier of the gene is 50% with each pregnancy. The likelihood of a child receiving normal genes from both parents and being considered to be "genetically" normal is 25%. The risk for carrying the gene is equivalent for both males and females.

"Alström syndrome (AS) is a rare autosomal recessive disease characterized by multiorgan dysfunction. The key features are childhood obesity, blindness due to congenital retinal dystrophy, and sensorineural hearing loss. Associated endocrinologic features include hyperinsulinemia, early-onset type 2 diabetes, and hypertriglyceridemia."

Thus, AS shares several features with the common metabolic syndrome, namely obesity, hyperinsulinemia, and hypertriglyceridemia. Mutations in the ALMS1 gene have been found to be causative for AS with a total of 79 disease-causing mutations having been described." Prevalence estimates have ranged from 1 in 10,000 to fewer than 1 in 1,000,000 individuals in the general population.