Upington disease, also called Perthes-like hip disease, enchondromata, ecchondromata, and familial dyschondroplasia, is an extremely rare autosomal dominant malformation disorder. It has only one published source claiming its existence in three generations of one family from South Africa.

The name Upington refers to the city in the Northern Cape Province, South Africa from where the family originates.

Lucey–Driscoll syndrome is an autosomal recessive metabolic disorder affecting enzymes involved in bilirubin metabolism. It is one of several disorders classified as a transient familial neonatal unconjugated hyperbilirubinemia.

Zori–Stalker–Williams syndrome, also known as pectus excavatum, macrocephaly, short stature and dysplastic nails, is a rare autosomal dominant congenital disorder associated with a range of features such as pectus excavatum, macrocephaly and dysplastic nails, familial short stature, developmental delay and distinctive facies. Further signs are known to be associated with this syndrome.

The name originates from the researchers who first defined and noticed the syndrome and its clinical signs.

It is believed that the syndrome is inherited in an autosomal dominant pattern, though there has been no new research undertaken for this rare disease.

A defect in the UGT1A1-gene, also linked to Crigler–Najjar syndrome and Gilbert's syndrome, is responsible for the congenital form of Lucey–Driscoll syndrome.

There is currently no cure for FD and death occurs in 50% of the affected individuals by age 30. There are only two treatment centers, one at New York University Hospital and one at the Sheba Medical Center in Israel. One is being planned for the San Francisco area.

The survival rate and quality of life have increased since the mid-1980s mostly due to a greater understanding of the most dangerous symptoms. At present, FD patients can be expected to function independently if treatment is begun early and major disabilities avoided.

A major issue has been aspiration pneumonia, where food or regurgitated stomach content would be aspirated into the lungs causing infections. Fundoplications (by preventing regurgitation) and gastrostomy tubes (to provide nonoral nutrition) have reduced the frequency of hospitalization.

Other issues which can be treated include FD crises, scoliosis, and various eye conditions due to limited or no tears.

An FD crisis is the body's loss of control of various autonomic nervous system functions including blood pressure, heart rate, and body temperature. Both short-term and chronic periodic high or low blood pressure have consequences and medication is used to stabilize blood pressure.

The outlook for patients with FD depends on the particular diagnostic category. Patients with chronic, progressive, generalized dysautonomia in the setting of central nervous system degeneration have a generally poor long-term prognosis. Death can occur from pneumonia, acute respiratory failure, or sudden cardiopulmonary arrest in such patients.

Parents and patients should generally be educated regarding daily eye care and early warning signs of corneal problems as well as the use of punctal cautery. This education has resulted in decreased corneal scarring and need for more aggressive surgical measures such as tarsorrhaphy, conjunctival flaps, and corneal transplants.

X-linked lymphoproliferative disease (also known as "Duncan's disease" or "Purtilo syndrome") is a lymphoproliferative disorder.

Berdon syndrome, also called Megacystis-microcolon-intestinal hypoperistalsis syndrome (MMIH syndrome), is an autosomal recessive fatal genetic disorder affecting newborns. In a 2011 study of 227 children with the syndrome, "the oldest survivor [was] 24 years old." The Ann Arbor News reported a five year old survivor at the end of 2015.

It is more prevalent in females, 7 females to 3 males, and is characterized by constipation and urinary retention, microcolon, giant bladder (megacystis), intestinal hypoperistalis, hydronephrosis, and dilated small bowel. The pathological findings consist of an abundance of ganglion cells in both dilated and narrow areas of the intestine. It is a familial disturbance of unknown cause.

Walter Berdon "et al." in 1976 first described the condition in five female infants, two of whom were sisters. All had marked dilatation of the bladder and some had hydronephrosis and the external appearance of prune belly. The infants also had microcolon and dilated small intestines.

HDL1 is an unusual, autosomal dominant familial prion disease. Only described in one family, it is caused by an eight-octapeptide repeat insertion in the "PRNP" gene. More broadly, inherited prion diseases in general can mimic HD.

Hereditary gelsolin amyloidosis is a cutaneous condition inherited in an autosomal dominant fashion.

The condition was first described in 1969, by the Finnish ophthalmologist Jouko Meretoja, and is also known as Familial amyloid neuropathy type IV, Meretoja syndrome, Hereditary amyloidosis, Finnish type.

The disorder primarily associated with eye, skin and cranial nerve symptoms. It is a form of amyloidosis, where the amyloid complexes are formed from fragments of the protein gelsolin in the plasma, due to a mutation in the GSN gene (c.654G>A or c.654G>T).

At present, no specific enzyme deficiency nor genetic mutation has been implicated as the cause of hypertryptophanemia. Several known factors regarding tryptophan metabolism and kynurenines, however, may explain the presence of behavioral abnormalities seen with the disorder.

Tryptophan is an essential amino acid, and is required for protein synthesis. Aside from this crucial role, the remainder of tryptophan is primarily metabolized along the kynurenine pathway in most tissues, including those of the brain and central nervous system.

As the main defect behind hypertryptophanemia is suspected to alter and disrupt the metabolic pathway from tryptophan to kynurenine, a possible correlation between hypertryptophanemia and the known effects of kynurenines on neuronal function, physiology and behavior may be of interest.

One of these kynurenines, aptly named kynurenic acid, serves as a neuroprotectant through its function as an antagonist at both nicotinic and glutamate receptors (responsive to the neurotransmitters nicotine and glutamate, respectively). This action is in opposition to the agonist quinolinic acid, another kynurenine, noted for its potential as a neurotoxin. Quinolinic acid activity has been associated with neurodegenerative disorders such as Huntington's disease, the neuroprective abilities of kynurenic acid forming a counterbalance against this process, and the related excitotoxicity and similar damaging effects on neurons.

Indoleic acid excretion is another indicator of hypertryptophanemia. Indirectly related to kynurenine metabolism, indole modifies neural function and human behavior by interacting with voltage-dependent sodium channels (integral membrane proteins that form ion channels, allowing vital synaptic action potentials).

The Huntington's disease-like syndromes (often abbreviated as HD-like or "HDL" syndromes) are a family of inherited neurodegenerative diseases that closely resemble Huntington's disease (HD) in that they typically produce a combination of chorea, cognitive decline or dementia and behavioural or psychiatric problems.

There is currently no cure for SCA 6; however, there are supportive treatments that may be useful in managing symptoms.

Infantile convulsions and choreoathetosis (ICCA) syndrome is a neurological genetic disorder with an autosomal dominant mode of inheritance. It is characterized by the association of benign familial infantile epilepsy (BIFE) at age 3–12 months and later in life with paroxysmal kinesigenic choreoathetosis. The ICCA syndrome was first reported in 1997 in four French families from north-western France and provided the first genetic evidence for common mechanisms shared by benign infantile seizures and paroxysmal dyskinesia. The epileptic origin of PKC has long been a matter of debates and PD have been classified as reflex epilepsies.Indeed, attacks of PKC and epileptic seizures have several characteristics in common, they both are paroxysmal in presentation with a tendency to spontaneous remission, and a subset of PKC responds well to anticonvulsants. This genetic disease has been mapped to chromosome 16p-q12. More than 30 families with the clinical characteristics of ICCA syndrome have been described worldwide so far.

Ischiopatellar dysplasia is sometimes referred to as Scott-Taor syndrome after the researchers who first described ischiopatellar dysplasia as they recognized it in a family as an autosomal dominant disorder in 1979. This finding was important as they were the first to note that it was a benign disorder that is separate from the more severe nail-patella syndrome. Other common names for ischiopatellar syndrome are small patella syndrome (SPS), since the patellae are often small or absent in patients who have this syndrome, and coxo-podo-patellaire syndrome.

X-linked reticulate pigmentary disorder (also known as "familial cutaneous amyloidosis", "Partington amyloidosis", "Partington cutaneous amyloidosis", "Partington syndrome type II", "reticulate pigmentary disorder", and "X-linked reticulate pigmentary disorder with systemic manifestations") is a cutaneous condition that has been described in adult women that had linear streaks of hyperpigmentation and in which male patients manifested a reticulated mottled brown pigmentation of the skin, which, on biopsy, demonstrated dermal deposits of amyloid.

The syndrome is also referred with the acronym X-Linked-PDR or even XLPRD.It's a very rare disease, genetically determined, with a chronic course.

It was characterized in 1981. Mutation of the "POLA1" gene leads to loss of expression of the catalytic subunit of DNA polymerase-α and is responsible for XLPDR. Loss of POLA1 expression results in reduced levels of RNA:DNA hybrids in the cytosol and unexpectedly triggers aberrant immune responses (e.g. type I interferon production) which at least in part can account for the symptoms associated with XLPDR.

Renal failure is the major cause of morbidity and mortality in complete LCAT deficiency, while in partial deficiency (fish eye disease) major cause of morbidity is visual impairment due to corneal opacity. These patients have low HDL cholesterol but surprisingly premature atherosclerosis is not seen. However, there are some reported cases.

In affected individuals presenting with the ICCA syndrome, the human genome was screened with microsatellite markers regularly spaced, and strong evidence of linkage with the disease was obtained in the pericentromeric region of chromosome 16, with a maximum lod score, for D16S3133 of 6.76 at a recombination fraction of 0. The disease gene has been mapped at chromosome 16p12-q12.This linkage has been confirmed by different authors. The chromosome 16 ICCA locus shows complicated genomic architecture and the ICCA gene remains unknown.

Hypertryptophanemia, also called familial hypertryptophanemia, is a rare autosomal recessive metabolic disorder that results in a massive buildup of the amino acid tryptophan in the blood, with associated symptoms and tryptophanuria ("-uria" denotes "in the urine").

Elevated levels of tryptophan are also seen in Hartnup disease, a disorder of amino acid transport. However, the increase of tryptophan in that disorder is negligible when compared to that of hypertryptophanemia.

Berdon syndrome is autosomal recessive, which means the defective gene is located on an autosome, and two copies of the gene - one inherited from each parent - are required to be born with the disorder. The parents of an individual with an autosomal recessive disorder both carry one copy of the defective gene, but are usually not affected by the disorder.

Several genes are known to be implicated in this syndrome: these include ACTG2, LMOD1, MYH11 and MYLK.

A team from the National Institute of Nutrition, Hyderabad conducted research in the affected regions and found out that the disease was confined to a dalit colony. They also found out that the disease was affecting people of all age groups and it was non-contagious and non-infectious. This research was further followed by research conducted over four years (1984–88) by the Indian Council of Medical Research (ICMR). Study groups involving experts from different medical fields were formed and these groups visited the affected places to conduct experiments. They were also helped by the Health Department of Karnataka who also provided a team to assist them. Despite undertaking extensive research, the team could not come into any conclusion on the cause of the disease. The team wound up in 1988 and this was the first phase of their research. The second phase of the research by ICMR was started in the year 2001 under the leadership of S. S. Agarwal of the Sanjay Gandhi Post-graduate centre in Lucknow. Some of the activities in the second phase were to x-ray the patients and also study their family history to see if the disease was related to genetics. The study reported that Handigodu syndrome is a syndrome of familial spondyloepi(meta)physeal dysplasia. It is inherited as an autosomal dominant trait. All the presentations of the varied manifestation of the disease could be explained as being caused by defective development of bones as a result of monogenic disorder.

Carbamazepine is at least partly effective at reducing the number or severity of attacks in the majority of PEPD patients. High doses of this drug may be required, perhaps explaining the lack of effect in some individuals. While other anti-epileptic drugs, gabapentin and topiramate, have limited effect in some patients, they have not been shown to be generally effective. Opiate derived analgesics are also largely ineffective, with only sporadic cases of beneficial effect.

There is no treatment, but because this is a benign condition with no serious clinical complications, prognosis is excellent.

The underlying lesion in this condition appears to be a mutation in the TTC7A gene. This gene is located on the short arm of chromosome 2 (2p16).