Meckel-Gruber syndrome is a rare, lethal ciliopathic genetic disorder, characterized by renal cystic dysplasia, central nervous system malformations, polydactyly (postaxial), hepatic developmental defects, and pulmonary hypoplasia due to oligohydramnios. Meckel–Gruber syndrome is named for Johann Meckel and Georg Gruber. This is called so because, of the following reasons.
Acrocallosal syndrome is an extremely rare autosomal recessive syndrome characterized by corpus callosum agenesis, polydactyly, multiple dysmorphic features, motor and intellectual disabilities, and other symptoms. The syndrome was first described by Albert Schinzel in 1979. Mutations in KIF7 are causative for ACLS, and mutations in GLI3 are associated with a similar syndrome.
Acropectoral syndrome is an autosomal dominant skeletal dysplasia syndrome affecting the hands, feet, sternum, and lumbosacral spine. A recently proposed candidate gene for preaxial polydactyly is LMBR1, encoding a novel transmembrane receptor, which may be an upstream regulator of SHH. The LMBR1 gene is on human chromosome 7q36.
Nager acrofacial dysostosis, also known as Nager syndrome, is a genetic disorder which displays several or all of the following characteristics: underdevelopment of the cheek and jaw area, down-sloping of the opening of the eyes, lack or absence of the lower eyelashes, kidney or stomach reflux, hammer toes, shortened soft palate, lack of development of the internal and external ear, possible cleft palate, underdevelopment or absence of the thumb, hearing loss and shortened forearms, as well as poor movement in the elbow, and may be characterized by accessory tragi. Occasionally, affected individuals develop vertebral anomalies such as scoliosis.
Cooks syndrome is a hereditary disorder which is characterized in the hands by bilateral nail hypoplasia on the thumb, index finger, and middle finger, absence of fingernails (anonychia) on the ring finger and little finger, lengthening of the thumbs, and bulbousness of the fingers. In the feet, it is characterized by absence of toenails and absence/hypoplasia of the distal phalanges. In the second study of this disorder, it was found that the intermediate phalanges, proximal phalanges, and metacarpals were unaffected.
Fryns syndrome is an autosomal recessive multiple congenital anomaly syndrome that is usually lethal in the neonatal period. Fryns (1987) reviewed the syndrome.
Young–Madders syndrome, alternatively known as Pseudotrisomy 13 syndrome or holoprosencephaly–polydactyly syndrome, is a genetic disorder resulting from defective and duplicated chromosomes which result in holoprosencephaly, polydactyly, facial malformations and intellectual disability, with a significant variance in the severity of symptoms being seen across known cases. Many cases often suffer with several other genetic disorders, and some have presented with hypoplasia, cleft lip, cardiac lesions and other heart defects. In one case in 1991 and another in 2000 the condition was found in siblings who were the product of incest. Many cases are diagnosed prenatally and often in siblings. Cases are almost fatal in the prenatal stage with babies being stillborn.
Ectrodactyly with tibia aplasia/hypoplasia also known as cleft hand absent tibia is a very rare limb malformation syndrome which is characterized by ectrodactyly, and aplasia/hypoplasia of the tibia bone. Additional findings include cup-shaped ears, pre-postaxial polydactyly, and hypoplasia of the big toes, femur, patella, and ulnae bone. It is inherited as an autosomal dominant trait with reduced penetrance.
Weyer's ulnar ray/oligodactyly syndrome is a rare multi-systemic genetic disorder which is characterized by ectrodactyly, ulnar, radial, or fibular ray deficit, and heart, single central incisor, splenic, and renal abnormalities. Cleft lip/palate and hypoplasia of the mandibles have also been observed. It is thought to be inherited in an autosomal recessive pattern. It was first discovered in 1957 by Weyers et al. Only four families worldwide are known to be affected by the disorder.
Chudley–Mccullough syndrome is a rare genetic disorder which is characterized by bilateral congenital hearing loss associated with brain malformations. It is a type of syndromic deafness.
Multiple congenital anomalies-hypotonia-seizures syndrome is a rare multi-systemic genetic disorder which is characterized by developmental delay, seizures, hypotonia and heart, urinary, and gastrointestinal abnormalities.
Santos–Mateus–Leal syndrome, also known as Hirschsprung's disease-deafness-polydactyly syndrome is a very rare autosomal recessive limb malformation which is characterized by Hirschsprung's disease, feet and hand polydactyly, unilateral renal agenesis, and congenital hearing loss. Only 2 cases have been described in medical literature.
Otofaciocervical syndrome, also known as Fara Chlupackova syndrome, are a small group of rare developmental disorders of genetic origin which are characterized by facial dysmorphisms, long neck, preauricular and/or branchial pits, cervical muscle hypoplasia, hearing loss, and mild intellectual disabilities. Additional findings include vertebral anomalies and short stature.
Wormian bone-multiple fractures-dentinogenesis imperfecta-skeletal dysplasia syndrome is a rare genetic bone disorder which is characterized by the presence of wormian bones in the skull, dentinogenesis imperfecta, recurrent bone fractures, hypertelorism, and eye puffiness. This disorder is unique from osteogenesis imperfecta because of the presence of cortical defects and the absence of defective collagen or osteopenia. It is not exactly known whether this condition is autosomal dominant or autosomal recessive.
Hall-Riggs syndrome is a rare genetic disorder that causes neurological issues and birth defects. People with Hall-Riggs syndrome usually have skeletal dysplasia, facial deformities, and intellectual disabilities. Only 8 cases from 2 families worldwide have been described in medical literature. It is an autosomal recessive genetic disorder, meaning both parents must carry the gene in order for their offspring to be affected.
Buttien-Fryns syndrome is a congenital genetic disorder that causes severe oligodactyly and micrognathia. It is caused by a change in the structure of the 10q gene. The condition has been reported in four patients, two of which were siblings.
