Respiratory complications are often cause of death in early infancy.

Marshall–Smith syndrome is not to be confused with:

- Marshall syndrome (aka.Periodic fever, aphthous stomatitis, pharyngitis and adenitis (PFAPA syndrome, see also: Periodic fever syndrome)

- Sotos (like) syndrome

- Weaver-Smith syndrome (WSS)

CHILD syndrome occurs almost exclusively in females. Only 2 known cases have been reported in males, one having a normal 46,XY karyotype, suggesting an early postzygotic somatic mutation.

Because CHILD syndrome is a congenital disorder, the symptoms may be present at birth or may develop during the first few weeks of life and continue for the lifetime of the patient.

Most patients with hyper IgE syndrome are treated with long-term antibiotic therapy to prevent staphylococcal infections. Good skin care is also important in patients with hyper IgE syndrome. High-dose intravenous gamma-globulin has also been suggested for the treatment of severe eczema in patients with HIES and atopic dermatitis.

As its name indicates, a person with the syndrome has one Y chromosome and four X chromosomes on the 23rd pair, thus having 49 chromosomes rather than the normal 46. As with most categories of aneuploidy disorders, 49,XXXXY syndrome is often accompanied by intellectual disability. It can be considered a form of 47, XXY Klinefelter syndrome, or a variant of it.

It is genetic but not hereditary. This means that while the genes of the parents cause the syndrome, there is a small chance of more than one child having the syndrome. The probability of inheriting the disease is about 1%.

The individuals with this syndrome are males, but 49, XXXXX also exists with similar characteristics.

As with most genetic diseases there is no way to prevent the entire disease. With prompt recognition and treatment of infections in childhood, the complications of low white blood cell counts may be limited.

It is thought to have an estimated incidence of 1 in 75,000 people.

Eiken syndrome is a rare autosomal bone dysplasia with a skeletal phenotype which has been described in a unique consanguineous family, where it segregates as a recessive trait.

Patterson syndrome, also called pseudoleprechaunism, is an extremely rare syndrome, first mistaken as Donohue Syndrome (also known as Leprechaunism).

It is named for Dr. Joseph Hanan Patterson. It was described by Patterson and Watkins in 1962.

The pathogenesis and cause of the Patterson syndrome was unknown until 1981.

Hyperimmunoglobulinemia E syndrome (HIES), of which the autosomal dominant form is called Job's syndrome or Buckley syndrome, is a heterogeneous group of immune disorders. Job's is also very rare at about 300 cases currently in the literature.

Kenny-Caffey syndrome is a rare genetic condition causing skeletal abnormalities. Individuals with the condition have a shortened stature and thickened long bones. Hypocalcemia is also common.

KCS is autosomal dominant and caused by a mutation in FAM111A. It affects males and females in equal proportion.

Treatment is based on symptoms.

Bangstad syndrome is a severe, inherited congenital disorder associated with abnormalities of the cell membrane.

It was characterized in 1989.

Some people may have some mental slowness, but children with this condition often have good social skills. Some males may have problems with fertility.

Presenting at birth, features of the disorder include moderately severe IUGR, microcephaly, craniosynostosis, moderately severe post uterine growth retardation, deafness, deep set eyes, cryptorchidism, truncal obesity and acanthosis nigricans, small teeth, prognathism, dislocated radial heads without generalized skeletal dysplasia, however, tall vertebrae, moderate mental retardation, hypothyroidism, insulin resistance, hypoparathyroidism.

Corneodermatosseous syndrome (also known as "CDO syndrome") is an autosomal dominant condition with onset in infancy, characterized by corneal dystrophy, photophobia, diffuse palmoplantar keratoderma, distal onycholysis, skeletal abnormalities, with brachydactyly, short stature, and medullary narrowing of digits.

Aase syndrome or Aase–Smith syndrome is a rare inherited disorder characterized by anemia with some joint and skeletal deformities. Aase syndrome is thought to be an autosomal recessive inherited disorder. The genetic basis of the disease is not known. The anemia is caused by underdevelopment of the bone marrow, which is where blood cells are formed.

It is named after the American paediatricians Jon Morton Aase and David Weyhe Smith, who characterized it in 1968.

This syndrome appears to be inherited in an autosomal dominant fashion.

Molecular analyses suggest that the causative mutations cause a truncation of the protein. These mutations result in the loss of PEST sequence in the protein. This loss is associated with a prolonged half life of the protein.

Mutations in Notch 3 were found to be associated with this syndrome.

Weissenbacher-Zweymüller syndrome affects males and females in the same numbers. About 30 cases have been reported in medical literature. This disorder can be underdiagnosed causing no true frequency in the population. Only 30 cases have been reported in medical literature.

Acro–dermato–ungual–lacrimal–tooth (ADULT) syndrome is a rare genetic disease. ADULT syndrome is an autosomal dominant form of ectodermal dysplasia, a group of disorders that affects the hair, teeth, nails, sweat glands, and extremities. The syndrome arises from a mutation in the TP63 gene. This disease was previously thought to be a form of ectrodactyly–ectodermal dysplasia–cleft syndrome (EEC), but was classified as a different disease in 1993 by Propping and Zerres.

Patterson syndrome is characterized by the patient's having an unusual facial look, similar to that caused by Leprechaunism. It primarily affects the connective tissue and the neuroendocrine system, giving rise to bronzed hyperpigmentation, cutis laxa of the hands and feet, bodily disproportion, severe mental retardation, and major bony deformities. Radiographs reveal a characteristic generalised skeletal dysplasia.

It comprises endocrine abnormality, hyperadrenocorticism, cushingoid features, and diabetes mellitus. One other case has shown premature adrenarche.

Seaver Cassidy syndrome is a very rare disorder characterized by certain facial, genital, and skeletal deformities, as well as an unusual susceptibility to bleeding. Seaver Cassidy syndrome was first described in 1991 by Laurie Seaver and Suzanne Cassidy.

One family of 68 individuals over 5 generations was studied and the prevalence of disease among the family members suggests that it is indicative of dominant inheritance that is not sexually linked. This is supported by the fact that the disease failed to skip generations even in the absence of intermarriages and that disease incidence was independent of sex. The current findings suggest that the cause of the disease could be narrowed down to one enzymatic defect that is involved in the development of neuroectodermal tissue, however the exact molecular mechanisms are currently unknown. The other symptoms that arise such as bone defects and diabetes may be secondary to this enzymatic defect.

Recent research has been focused on studying large series of cases of 3-M syndrome to allow scientists to obtain more information behind the genes involved in the development of this disorder. Knowing more about the underlying mechanism can reveal new possibilities for treatment and prevention of genetic disorders like 3-M syndrome.

- One study looks at 33 cases of 3M syndrome, 23 of these cases were identified as CUL7 mutations: 12 being homozygotes and 11 being heterozygotes. This new research shows genetic heterogeneity in 3M syndrome, in contrast to the clinical homogeneity. Additional studies are still ongoing and will lead to the understanding of this new information.

- This study provides more insight on the three genes involved in 3M syndrome and how they interact with each other in normal development. It lead to the discovery that the CUL7, OBS1, and CCDC8 form a complex that functions to maintain microtubule and genomic integrity.

3-M syndrome is most often caused by a mutation in the gene CUL7, but can also be seen with mutations in the genes OBS1 and CCDC8 at lower frequencies. This is an inheritable disorder and can be passed down from parent to offspring in an autosomal recessive pattern. An individual must receive two copies of the mutated gene, one from each parent, in order to be have 3-M syndrome. An individual can be a carrier for the disorder if they inherit only one mutant copy of the gene, but will not present any of the symptoms associated with the disorder.

Since 3-M syndrome is a genetic condition there are no known methods to preventing this disorder. However, genetic testing on expecting parents and prenatal testing, which is a molecular test that screens for any problems in the heath of a fetus during pregnancy, may be available for families with a history of this disorder to determine the fetus' risk in inheriting this genetic disorder.