A review from 2000 stated that life expectancy was reduced because of a tendency to develop cancer relatively early as well as deaths due to infections related to immunodeficiency.

Roberts syndrome is an extremely rare condition that only affects about 150 reported individuals. Although there have been only about 150 reported cases, the affected group is quite diverse and spread worldwide. Parental consanguinity (parents are closely related) is common with this genetic disorder. The frequency of Roberts syndrome carriers is unknown.

Bloom syndrome is an extremely rare disorder in most populations and the frequency of the disease has not been measured in most populations. However, the disorder is relatively more common amongst people of Central and Eastern European (Ashkenazi) Jewish background. Approximately 1 in 48,000 Ashkenazi Jews are affected by Bloom syndrome, who account for about one-third of affected individuals worldwide.

In itself, NSML is not a life-threatening diagnosis, most people diagnosed with the condition live normal lives. Obstructive cardiomyopathy and other pathologic findings involving the cardiovascular system may be a cause of death in those whose cardiac deformities are profound.

Griscelli syndrome type 2 (also known as "partial albinism with immunodeficiency") is a rare autosomal recessive syndrome characterized by variable pigmentary dilution, hair with silvery metallic sheen, frequent pyogenic infections, neutropenia, and thrombocytopenia.

Bloom syndrome (often abbreviated as BS in literature), also known as Bloom-Torre-Machacek syndrome, is a rare autosomal recessive disorder characterized by short stature, predisposition to the development of cancer and genomic instability. BS is caused by mutations in the BLM gene leading to mutated DNA helicase protein formation. Cells from a person with Bloom syndrome exhibit a striking genomic instability that includes excessive crossovers between homologous chromosomes and sister chromatid exchanges (SCEs). The condition was discovered and first described by New York dermatologist Dr. David Bloom in 1954.

It is possible to acquire this disease later in life.

Causes include ingesting expired tetracyclines (where tetracycline changes to form epitetracycline and anhydrotetracycline which damage proximal tubule), and as a side effect of tenofovir in cases of pre-existing renal impairment. In the HIV population, Fanconi syndrome can develop secondary to the use of an antiretroviral regimen containing tenofovir and didanosine.

Lead poisoning also leads to Fanconi syndrome.

Multiple myeloma or monoclonal gammopathy of undetermined significance can also cause the condition.

Additionally, Fanconi Syndrome can develop as a secondary or tertiary effect of certain autoimmune disorders.

Recent findings in genetic research have suggested that a large number of genetic disorders, both genetic syndromes and genetic diseases, that were not previously identified in the medical literature as related, may be, in fact, highly related in the genetypical root cause of the widely varying, phenotypically-observed disorders. Thus, Alstrom syndrome is a ciliopathy. Other known ciliopathies include primary ciliary dyskinesia, Bardet-Biedl syndrome, polycystic kidney and liver disease, nephronophthisis, Meckel-Gruber syndrome and some forms of retinal degeneration.

Prevention for Alström Syndrome is considered to be harder compared to other diseases/syndromes because it is an inherited condition. However, there are other options that are available for parents with a family history of Alström Syndrome. Genetic testing and counseling are available where individuals are able to meet with a genetic counselor to discuss risks of having the children with the disease. The genetic counselor may also help determine whether individuals carry the defective ALSM1 gene before the individuals conceive a child. Some of the tests the genetic counselors perform include chorionic villus sampling (CVS), Preimplantation genetic diagnosis (PGD), and amniocentesis. With PGD, the embryos are tested for the ALSM1 gene and only the embryos that are not affected may be chosen for implantation via in vitro fertilization.

Nijmegen breakage syndrome (NBS), also known as Berlin breakage syndrome, ataxia telangiectasia variant 1 (AT-V1) and Seemanova syndrome, is a rare autosomal recessive congenital disorder causing chromosomal instability, probably as a result of a defect in the double Holliday junction DNA repair mechanism and/or the synthesis dependent strand annealing mechanism for repairing double strand breaks in DNA (see Homologous recombination).

NBS1 codes for a protein (nibrin) that has two major functions: (1) to stop the cell cycle in the S phase, when there are errors in the cell DNA (2) to interact with FANCD2 that can activate the BRCA1/BRCA2 pathway of DNA repair. This explains why mutations in the NBS1 gene lead to higher levels of cancer (see Fanconi anemia, Cockayne syndrome.)

The name derives from the Dutch city Nijmegen where the condition was first described.

Most people with NBS have West Slavic origins. The largest number of them live in Poland.

This includes Chediak-Higashi syndrome and Elejalde syndrome (neuroectodermal melanolysosomal disease).

Chromosome instability syndromes are a group of inherited conditions associated with chromosomal instability and breakage. They often lead to an increased tendency to develop certain types of malignancies.

The following chromosome instability syndromes are known:

- Ataxia telangiectasia

- Ataxia telangiectasia-like disorder

- Bloom syndrome

- Fanconi anaemia

- Nijmegen breakage syndrome

At this time, there are no other phenotypes (observable expressions of a gene) that have been discovered for mutations in the ESCO2 gene.

Because oculocerebrorenal syndrome is an X-linked recessive condition, the disease develops mostly in men with very rare occurrences in women, while women are carriers of the disease; it has an estimated prevalence of 1 in 500,000 people. Boys with Lowe syndrome are born with cataracts in both eyes, glaucoma is present in about half of the individuals with Lowe syndrome, though usually not at birth. While not present at birth, many affected boys develop kidney problems at about one year of age. Renal pathology is characterized by an abnormal loss of certain substances into the urine, including bicarbonate, sodium, potassium, amino acids, organic acids, albumin, calcium and L-carnitine, this problem, is known as Fanconi-type renal tubular dysfunction.

In the two predominant mutations of NSML (Y279C and T468M) the mutations cause a loss of catalytic activity of the SHP2 protein (the gene product of the "PTPN11" gene), which is a previously unrecognized behavior for this class of mutations. This interferes with growth factor and related signalling. While further research confirms this mechanism, additional research is needed to determine how this relates to all of the observed effects of NSML.

The incidence of Fraser syndrome is 0.043 per 10,000 live born infants and 1.1 in 10,000 stillbirths, making it a rare syndrome.

Cystinosis is the most common cause of Fanconi syndrome in children.

Other recognised causes are Wilson's disease (a genetically inherited condition of copper metabolism), Lowe syndrome, tyrosinemia (type I), galactosemia, glycogen storage diseases, and hereditary fructose intolerance.

Two forms, Dent's disease and Lowe syndrome, are X linked.

A recently described form of this disease is due to a mutation in the peroxisomal protein EHHADH. This mutation misdirects the EHHADH to the mitochondria. This interfers with respiratory complex I and with beta oxidation of fatty acids. The end result is a decrease in the ability of the mitochondria to produce ATP.

Children with Pfeiffer syndrome types 2 and 3 "have a higher risk for neurodevelopmental disorders and a reduced life expectancy" than children with Pfeiffer syndrome type 1, but if treated, favorable outcomes are possible. In severe cases, respiratory and neurological complications often lead to early death.

Oculocerebrorenal syndrome (also called Lowe syndrome) is a rare X-linked recessive disorder characterized by congenital cataracts, hypotonia, intellectual disability, proximal tubular acidosis, aminoaciduria, and low-molecular-weight proteinuria. Lowe syndrome can be considered a cause of Fanconi syndrome (bicarbonaturia, renal tubular acidosis, potassium loss, and sodium loss).

Many patients eventually develop acute myelogenous leukemia (AML). Older patients are extremely likely to develop head and neck, esophageal, gastrointestinal, vulvar and anal cancers. Patients who have had a successful bone marrow transplant and, thus, are cured of the blood problem associated with FA still must have regular examinations to watch for signs of cancer. Many patients do not reach adulthood.

The overarching medical challenge that Fanconi patients face is a failure of their bone marrow to produce blood cells. In addition, Fanconi patients normally are born with a variety of birth defects. A good number of Fanconi patients have kidney problems, trouble with their eyes, developmental retardation and other serious defects, such as microcephaly (small head).

The RASopathies are developmental syndromes caused by germline mutations (or in rare cases by somatic mosaicism) in genes that alter the Ras subfamily and mitogen-activated protein kinases that control signal transduction, including:

- Capillary malformation-AV malformation syndrome

- Autoimmune lymphoproliferative syndrome

- Cardiofaciocutaneous syndrome

- Hereditary gingival fibromatosis type 1

- Neurofibromatosis type 1

- Noonan syndrome

- Costello syndrome, Noonan-like

- Legius syndrome, Noonan-like

- Noonan syndrome with multiple lentigines, formerly called LEOPARD syndrome, Noonan-like

TBS is an autosomal dominant involving the a mutation of the gene SALL1, which encodes a transcriptional repressor which interacts with TRF1/PIN2 and localizes to pericentromeric heterochromatin. The clinical features of TBS overlap with VATER and VACTERL associations, oculo-auriculo-vertebral (OAV) spectrum, branchio-oto-renal (BOR) syndrome, and Fanconi anemia and other 'anus-hand-ear' syndromes.

Although some symptoms can be life-threatening, many people diagnosed with Townes-Brocks Syndrome live a normal lifespan.

The first line of therapy is androgens and hematopoietic growth factors, but only 50-75% of patients respond. A more permanent cure is hematopoietic stem cell transplantation. If no potential donors exist, a savior sibling can be conceived by preimplantation genetic diagnosis (PGD) to match the recipient's HLA type.

Most pedigrees suggest an autosomal dominant mode of inheritance with incomplete penetrance. Approximately 10–25% of DBA occurs with a family history of disease.

About 25-50% of the causes of DBA have been tied to abnormal ribosomal protein genes. The disease is characterized by genetic heterogeneity, affecting different ribosomal gene loci: Exceptions to this paradigm have been demonstrated, such as with rare mutations of transcription factor GATA1 and advanced alternative splicing of a gene involved in iron metabolism, SLC49A1 (FLVCR1).

In 1997, a patient was identified who carried a rare balanced chromosomal translocation involving chromosome 19 and the X chromosome. This suggested that the affected gene might lie in one of the two regions that were disrupted by this cytogenetic anomaly. Linkage analysis in affected families also implicated this region in disease, and led to the cloning of the first DBA gene. About 20–25% of DBA cases are caused by mutations in the ribosome protein S19 (RPS19) gene on chromosome 19 at cytogenetic position 19q13.2. Some previously undiagnosed relatives of DBA patients were found to carry mutations, and also had increased adenosine deaminase levels in their red blood cells, but had no other overt signs of disease.

A subsequent study of families with no evidence of RPS19 mutations determined that 18 of 38 families showed evidence for involvement of an unknown gene on chromosome 8 at 8p23.3-8p22. The precise genetic defect in these families has not yet been delineated.

Malformations are seen more frequently with DBA6 RPL5 and DBA7 RPL11 mutations.

The genetic abnormalities underpinning the combination of DBA with Treacher Collins syndrome (TCS)/mandibulofacial dysostosis (MFD) phenotypes are heterogeneous, including RPS26 (the known DBA10 gene), TSR2 which encodes a direct binding partner of RPS26, and RPS28.

Phagocytes are the cells that engulf and ingest pathogens (phagocytosis), and destroy them with chemicals. Monocytes/macrophages as well as granulocytes are capable of this process. In certain conditions, either the number of phagocytes is reduced or their functional capacity is impaired.

1. Severe Congenital Neutropenia: due to ELA2 deficiency (with myelodysplasia)

2. Severe Congenital Neutropenia: due to GFI1 deficiency (with T/B lymphopenia)

3. Kostmann syndrome

4. Neutropenia with cardiac and urogenital malformations

5. Glycogen storage disease type 1b

6. Cyclic neutropenia

7. X-linked neutropenia/myelodysplasia

8. P14 deficiency

9. Leukocyte adhesion deficiency type 1

10. Leukocyte adhesion deficiency type 2

11. Leukocyte adhesion deficiency type 3

12. RAC2 deficiency (Neutrophil immunodeficiency syndrome)

13. Beta-actin deficiency

14. Localized juvenile periodontitis

15. Papillon–Lefèvre syndrome

16. Specific granule deficiency

17. Shwachman–Diamond syndrome

18. Chronic granulomatous disease: X-linked

19. Chronic granulomatous disease: autosomal ("CYBA")

20. Chronic granulomatous disease: autosomal ("NCF1")

21. Chronic granulomatous disease: autosomal ("NCF2")

22. IL-12 and IL-23 β1 chain deficiency

23. IL-12p40 deficiency

24. Interferon γ receptor 1 deficiency

25. Interferon γ receptor 2 deficiency

26. STAT1 deficiency (2 forms)

27. AD hyper-IgE

28. AR hyper-IgE

29. Pulmonary alveolar proteinosis