The cause of Goldenhar syndrome is largely unknown. However, it is thought to be multifactorial, although there may be a genetic component, which would account for certain familial patterns. It has been suggested that there is a branchial arch development issue late in the first trimester.

An increase in Goldenhar syndrome in the children of Gulf War veterans has been suggested, but the difference was shown to be statistically insignificant.

Although no cause has been officially confirmed, researchers speculate the disease might result from a genetic mutation that sporadically occurs for unknown reasons.

The inheritance of Impossible syndrome is suspected to be autosomal recessive, which means the affected gene is located on an autosome, and two copies of the gene - one from each parent - are required to have an infant with the disorder.

Patients with abnormal cardiac and kidney function may be more at risk for hemolytic uremic syndrome

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.

Prevalence ranges from 1 in 3500 to 5600 live births. Male-female ratio is found to be 3:2.

There are approximately three hundred known cases of Carpenter Syndrome in the United States. Only 1 in 1 million live births will result in an infant affected by Carpenter Syndrome (RN, 2007).

Carpenter Syndrome is an autosomal recessive disease which means both parents must have the faulty genes in order to pass the disease onto their children. Even if both parents possess the faulty gene there is still only a twenty five percent chance that they will produce a child affected by the syndrome. Their children who do not have the disease will still be carriers and possess the ability to pass the disease onto their offspring if their spouse is also a carrier of the particular gene.

While not precisely known, it is estimated that the general rate of incidence, according to Bergsma, for Meckel syndrome is 0.02 per 10,000 births. According to another study done six years later, the incidence rate could vary from 0.07 to 0.7 per 10,000 births.

This syndrome is a Finnish heritage disease. Its frequency is much higher in Finland, where the incidence is as high as 1.1 per 10,000 births. It is estimated that Meckel syndrome accounts for 5% of all neural tube defects there.

Medical conditions include frequent ear infection, hearing loss, hypotonia, developmental problems, respiratory problems, eating difficulties, light sensitivity, and esophageal reflux.

Data on fertility and the development of secondary sex characteristics is relatively sparse. It has been reported that both male and female patients have had children. Males who have reproduced have all had the autosomal dominant form of the disorder; the fertility of those with the recessive variant is unknown.

Researchers have also reported abnormalities in the renal tract of affected patients. Hydronephrosis is a relatively common condition, and researchers have theorized that this may lead to urinary tract infections. In addition, a number of patients have suffered from cystic dysplasia of the kidney.

A number of other conditions are often associated with Robinow syndrome. About 15% of reported patients suffer from congenital heart defects. Though there is no clear pattern, the most common conditions include pulmonary stenosis and atresia. In addition, though intelligence is generally normal, around 15% of patients show developmental delays.

The incidence of VACTERL association is estimated to be approximately 1 in 10,000 to 1 in 40,000 live-born infants. It is seen more frequently in infants born to diabetic mothers. While most cases are sporadic, there are clearly families who present with multiple involved members.

Majewski's polydactyly syndrome, also known as polydactyly with neonatal chondrodystrophy type I, short rib-polydactyly syndrome type II, and short rib-polydactyly syndrome, is a lethal form of neonatal dwarfism characterized by osteochondrodysplasia (skeletal abnormalities in the development of bone and cartilage) with a narrow thorax, polysyndactyly, disproportionately short tibiae, thorax dysplasia, hypoplastic lungs and respiratory insufficiency. Associated anomalies include protruding abdomen, brachydactyly, peculiar faces, hypoplastic epiglottis, cardiovascular defects, renal cysts, and also genital anomalies. Death occurs before or at birth.

The disease is inherited in an autosomal recessive pattern.

It was characterized in 1971.

The prevalence of Klippel–Feil syndrome is unknown due to the fact that there was no study done to determine the true prevalence.

Although the actual occurrence for the KFS syndrome is unknown, it is estimated to occur 1 in 40,000 to 42,000 newborns worldwide. In addition, females seem to be affected slightly more often than males.

Until recently, the medical literature did not indicate a connection among many genetic disorders, both genetic syndromes and genetic diseases, that are now being found to be related. As a result of new genetic research, some of these are, in fact, highly related in their root cause despite the widely varying set of medical symptoms that are clinically visible in the disorders. Ellis–van Creveld syndrome is one such disease, part of an emerging class of diseases called ciliopathies. The underlying cause may be a dysfunctional molecular mechanism in the primary cilia structures of the cell, organelles which are present in many cellular types throughout the human body. The cilia defects adversely affect "numerous critical developmental signaling pathways" essential to cellular development and thus offer a plausible hypothesis for the often multi-symptom nature of a large set of syndromes and diseases. Known ciliopathies include primary ciliary dyskinesia, Bardet–Biedl syndrome, polycystic kidney and liver disease, nephronophthisis, Alstrom syndrome, Meckel–Gruber syndrome and some forms of retinal degeneration.

Weyers acrofacial dysostosis is due to another mutation in the EVC gene and hence is allelic with Ellis–van Creveld syndrome.

Ellis–van Creveld syndrome often is the result of founder effects in isolated human populations, such as the Amish and some small island inhabitants. Although relatively rare, this disorder does occur with higher incidence within founder-effect populations due to lack of genetic variability. Observation of the inheritance pattern has illustrated that the disease is autosomal recessive, meaning that both parents have to carry the gene in order for an individual to be affected by the disorder.

Ellis–van Creveld syndrome is caused by a mutation in the "EVC" gene, as well as by a mutation in a nonhomologous gene, "EVC2", located close to the EVC gene in a head-to-head configuration. The gene was identified by positional cloning. The EVC gene maps to the chromosome 4 short arm (4p16). The function of a healthy EVC gene is not well understood at this time.

Impossible Syndrome, or Chondrodysplasia situs inversus imperforate anus polydactyly, is a complex combination of human congenital malformations (birth defects).

The malformations include chondrodysplasia (improper growth of bone and cartilage), situs inversus totalis (chest and abdominal organs all a mirror image of normal), cleft larynx and epiglottis, hexadactyly (six digits) on hands and feet, diaphragmatic hernia, pancreatic abnormalities, kidney abnormal on one side and absent on the other side, micropenis and ambiguous genitalia, and imperforate anus.

Only one case of Impossible Syndrome has been reported; the infant was premature and stillborn.

Genetic studies have linked the autosomal recessive form of the disorder to the "ROR2" gene on position 9 of the long arm of chromosome 9. The gene is responsible for aspects of bone and cartilage growth. This same gene is involved in causing autosomal dominant brachydactyly B.

The autosomal dominant form has been linked to three genes - WNT5A, Segment polarity protein dishevelled homolog DVL-1 (DVL1) and Segment polarity protein dishevelled homolog DVL-3 (DVL3). This form is often caused by new mutations and is generally less severe then the recessive form. Two further genes have been linked to this disorder - Frizzled-2 (FZD2) and Nucleoredoxin (NXN gene). All of these genes belong to the same metabolic pathway - the WNT system. This system is involved in secretion for various compounds both in the fetus and in the adult.

A fetal ultrasound can offer prenatal diagnosis 19 weeks into pregnancy. However, the characteristics of a fetus suffering from the milder dominant form may not always be easy to differentiate from a more serious recessive case. Genetic counseling is an option given the availability of a family history.

Carpenter syndrome has been associated with mutations in the RAB23 gene, which is located on chromosome 6 in humans. Additionally, three key SNPs in the MEGF8 gene, located on chromosome 19 at 19q13.2, have been identified as primary causes of Carpenter syndrome.

McKusick–Kaufman syndrome is a genetic condition associated with MKKS.

The condition is named for Dr. Robert L. Kaufman and Victor McKusick. It is sometimes known by the abbreviation MKS. In infancy it can be difficult to distinguish between MKS and the related Bardet–Biedl syndrome, as the more severe symptoms of the latter condition rarely materialise before adulthood.

The varied signs and symptoms of Duane-radial ray syndrome often overlap with features of other disorders.

- For example, acro-renal-ocular syndrome is characterized by Duane anomaly and other eye abnormalities, radial ray malformations, and kidney defects. Both conditions can be caused by mutations in the same gene. Based on these similarities, researchers are investigating whether Duane-radial ray syndrome and acro-renal-ocular syndrome are separate disorders or part of a single syndrome with many possible signs and symptoms.

- The features of Duane-radial ray syndrome also overlap with those of a condition called Holt-Oram syndrome; however, these two disorders are caused by mutations in different genes.

It has several different types:

- type 1 - Apert syndrome

- type 2 - Crouzon syndrome

- type 3 - Saethre-Chotzen syndrome

- type 5 - Pfeiffer syndrome

A related term, "acrocephalopolysyndactyly" (ACPS), refers to the inclusion of polydactyly to the presentation. It also has multiple types:

- type 1 - Noack syndrome; now classified with Pfeiffer syndrome

- type 2 - Carpenter syndrome

- type 3 - Sakati-Nyhan-Tisdale syndrome

- type 4 - Goodman syndrome; now classified with Carpenter syndrome

- type 5 - Pfeiffer syndrome

It has been suggested that the distinction between "acrocephalosyndactyly" versus "acrocephalopolysyndactyly" should be abandoned.

Tetra-amelia syndrome ("" + "amelia"), also called autosomal recessive tetraamelia, is an extremely rare autosomal recessive congenital disorder characterized by the absence of all four limbs. Other areas of the body are also affected by malformations, such as the face, skull, reproductive organs, anus and pelvis. The disorder is caused by mutations in the WNT3 gene.

Acrocephalosyndactylia (or acrocephalosyndactyly) is the common presentation of craniosynostosis and syndactyly.

Meckel syndrome (also known as Meckel–Gruber Syndrome, Gruber Syndrome, Dysencephalia Splanchnocystica) is a rare, , ciliopathic, genetic disorder, characterized by renal cystic dysplasia, central nervous system malformations (occipital encephalocele), polydactyly (post axial), hepatic developmental defects, and pulmonary hypoplasia due to oligohydramnios.

Meckel–Gruber syndrome is named for Johann Meckel and Georg Gruber.

Three main support groups of this syndrome are the ASGA in Australia, The Association for Children with Genetic Disorders in Poland, and the Association of People of Genetic Disorders in Greece.

Miller syndrome is a genetic condition also known as the Genee–Wiedemann syndrome, Wildervanck–Smith syndrome, or postaxial acrofacial dystosis. The incidence of this condition is not known, but it is considered extremely rare. It is due to a mutation in the DHODH gene. Nothing is known of its pathogenesis.