Mucolipidosis IV (MLIV) is an ultra-rare lysosomal storage disorder characterized by severe psychomotor delay, progressive visual impairment, and achlorhydria. Individuals with MLIV typically present by the end of the first year of life with delayed developmental milestones (due to a developmental brain abnormality) and impaired vision (resulting from a combination of corneal clouding and retinal degeneration). By adolescence, all individuals with MLIV have severe visual impairment. A neurodegenerative component of MLIV has become more widely appreciated, with the majority of individuals demonstrating progressive spastic quadriparesis and loss of psychomotor skills starting in the second decade of life. About 5% of individuals have atypical MLIV, manifesting with less severe psychomotor impairment, but still exhibiting progressive retinal degeneration and achlorhydria.

Jejunal atresia is the most common cause of bowel obstruction in the newborn. In this condition, because of agenesis of the mesentery, the distal small bowel comes straight off the caecum and twists around the marginal artery, suggesting a maypole, a Christmas tree, or an apple peel at operation. Obliteration of the superior mesenteric artery may underlie this malformation.

A developmental defect in which the gallbladder fails to form.

Blue Diaper syndrome is a hereditary metabolic disorder characterised by hypercalcaemia with nephrocalcinosis and indicanuria.

Juberg-Hayward syndrome (JHS) is characterized by cleft lip and palate, rhizomelia of the upper limbs with limited elbow extension due to humeroradial synostosis or dislocation of the radial head, and digital anomalies, including shortened thumbs and index and fifth fingers. Microcephaly has been observed in some patients (Kantaputra et al., 2020).

The Finnish type of systemic amyloidosis is characterized clinically by a unique constellation of features including lattice corneal dystrophy, and cranial neuropathy, bulbar signs, and skin changes. Some patients may develop peripheral neuropathy and renal failure. The disorder is usually inherited in an autosomal dominant pattern; however, homozygotes with a more severe phenotype have also been reported (Meretoja, 1973).

The hereditary mixed polyposis syndrome (HMPS) is characterized by atypical juvenile polyps, colonic adenomas, and colorectal carcinomas (CRC). Genetic Heterogeneity of Hereditary Mixed Polyposis HMPS2 (610069) is caused by mutation in the BMPR1A gene (601299) on chromosome 10q23.

Graves' disease is a condition that affects the function of the thyroid, which is a butterfly-shaped gland in the lower neck. The thyroid makes hormones that help regulate a wide variety of critical body functions. For example, thyroid hormones influence growth and development, body temperature, heart rate, menstrual cycles, and weight. In people with Graves' disease, the thyroid is overactive and makes more hormones than the body needs. The condition usually appears in mid-adulthood, although it may occur at any age.\n\nExcess thyroid hormones can cause a variety of signs and symptoms. These include nervousness or anxiety, extreme tiredness (fatigue), a rapid and irregular heartbeat, hand tremors, frequent bowel movements or diarrhea, increased sweating and difficulty tolerating hot conditions, trouble sleeping, and weight loss in spite of an increased appetite. Affected women may have menstrual irregularities, such as an unusually light menstrual flow and infrequent periods. Some people with Graves' disease develop an enlargement of the thyroid called a goiter. Depending on its size, the enlarged thyroid can cause the neck to look swollen and may interfere with breathing and swallowing.\n\nBetween 25 and 50 percent of people with Graves' disease have eye abnormalities, which are known as Graves' ophthalmopathy. These eye problems can include swelling and inflammation, redness, dryness, puffy eyelids, and a gritty sensation like having sand or dirt in the eyes. Some people develop bulging of the eyes caused by inflammation of tissues behind the eyeball and "pulling back" (retraction) of the eyelids. Rarely, affected individuals have more serious eye problems, such as pain, double vision, and pinching (compression) of the optic nerve connecting the eye and the brain, which can cause vision loss.\n\nA small percentage of people with Graves' disease develop a skin abnormality called pretibial myxedema or Graves' dermopathy. This abnormality causes the skin on the front of the lower legs and the tops of the feet to become thick, lumpy, and red. It is not usually painful.

A rare genetic skin disorder with characteristics of very early-onset of progressive skin thickening over the entire body (except for eyelids, neck and ears), progressively limited joint mobility with gradual freezing of joints and eventual severe chest and abdomen movement restriction, manifesting with restrictive pulmonary disease, which may lead to death. Additional features include severe growth restriction and osteoporosis. There have been no further descriptions in the literature since 1974.

A rare multiple congenital anomalies/dysmorphic syndrome characterized by auditory canal atresia (resulting in moderate conductive hearing loss) associated with intellectual disability, ventricular septal defect, umbilical hernia, anteriorly displaced anus, various skeletal anomalies (such as mild clubfoot, long fifth fingers, proximally placed thumbs), and craniofacial dysmorphism which includes brachycephaly, prominent forehead, flattened occiput, midface hypoplasia, anteverted nares, and low set, posteriorly rotated ears with overlapping superior helix. There have been no further descriptions in the literature since 1987.

Systemic sclerosis is a clinically heterogeneous connective tissue disorder characterized by immune activation, vascular damage, and fibrosis of the skin and major internal organs. Clinical and experimental data suggest that the disorder is multifactorial, involving both genetic and environmental factors (Fonseca et al., 2007). Gabrielli et al. (2009) provided a detailed review of scleroderma, including clinical manifestations and pathophysiology. See also Reynolds syndrome (613471), which shares some clinical features with scleroderma and CREST syndrome.

Any COACH syndrome in which the cause of the disease is a variation in the TMEM67 gene.

Developmental delay, impaired speech, and behavioral abnormalities (DDISBA) is characterized by global developmental delay apparent from early childhood. Intellectual disability can range from mild to severe. Additional variable features may include dysmorphic facial features, seizures, hypotonia, motor abnormalities such as Tourette syndrome or dystonia, and hearing loss (summary by Cousin et al., 2021).