Griscelli syndrome type 2 (also known as "partial albinism with immunodeficiency") is a rare autosomal recessive syndrome characterized by variable cutenous albinism, silver colored metallic looking hair, frequent bacterial or viral infections,
neutropenia, and
thrombocytopenia
Thrombocytopenia is a condition characterized by abnormally low levels of platelets, also known as thrombocytes, in the blood. It is the most common coagulation disorder among intensive care patients and is seen in a fifth of medical patients a ...
.
[James, William; Berger, Timothy; Elston, Dirk (2005). ''Andrews' Diseases of the Skin: Clinical Dermatology''. (10th ed.). Saunders. .]
Presentation
All types of Griscelli syndrome have distinctive skin and hair coloring.
Type 1 is associated with neurological abnormalities. These include delayed development, intellectual disability, seizures, hypotonia and eye abnormalities.
Type 2 - unlike type 1 - is not associated with primary neurological disease but is associated with an uncontrolled T
lymphocyte
A lymphocyte is a type of white blood cell (leukocyte) in the immune system of most vertebrates. Lymphocytes include natural killer cells (which function in cell-mediated, cytotoxic innate immunity), T cells (for cell-mediated, cytotoxic ad ...
expansion and
macrophage activation syndrome. It is often associated with the
hemophagocytic syndrome. This latter condition may be fatal in the absence of bone marrow transplantation.
Persons with type 3 have the typical light skin and hair coloring but are otherwise normal.
Genetics
There are three types of Griscelli syndrome.
Type 1 is associated with mutations in the
MYO5A
Unconventional myosin-Va is a motor protein in charge of the intracellular transport of vesicles, organelles and protein complexes along the actin filaments. In humans it is coded for by the ''MYO5A'' gene.
Structure
In the presence of cargo ada ...
gene
Type 2 is associated with mutations in
RAB27A
Ras-related protein Rab-27A is a protein that in humans is encoded by the ''RAB27A'' gene.
Function
The protein encoded by this gene belongs to the small GTPase superfamily, Rab family. The protein is membrane-bound and may be involved in prot ...
gene.
Both these genes are located on the long arm of
chromosome 15
Chromosome 15 is one of the 23 pairs of chromosomes in humans. People normally have two copies of this chromosome. Chromosome 15 spans about 102 million base pairs (the building material of DNA) and represents between 3% and 3.5% of the total DN ...
(15q21).
Type 3 is associated with mutations in the
MLPH gene.
All types are inherited in an autosomal recessive fashion.
Diagnosis
Differential diagnosis
This includes
Chediak-Higashi syndrome and
Elejalde syndrome
Elejalde syndrome or neuroectodermal melanolysosomal disease is an extremely rare autosomal recessive syndrome (only around 10 cases known) consisting of moderate pigment dilution, profound central nervous system dysfunction, no immune defects, ...
(neuroectodermal melanolysosomal disease).
Treatment
History
This syndrome was first described in 1978.
[Griscelli C, Durandy, A, Guy-Grand D, Daguillard F, Herzog C, Prunieras M (1978) A syndrome associating partial albinism and immunodeficiency. Am J Med 65:691-702] In 2000 types 1 and 2 were distinguished.
[Menasche G, Pastural E, Feldmann J, Certain S, Ersoy F, Dupuis S, Wulffraat N, Bianchi D, Fischer A, Le Deist F, de Saint Basile G (2000) Mutations in RAB27A cause Griscelli syndrome associated with haemophagocytic syndrome. Nature Genet 25:173-176]
See also
*
Griscelli syndrome
Griscelli syndrome is a rare autosomal recessive disorder characterized by albinism (hypopigmentation) with immunodeficiency, that usually causes death by early childhood. Researchers have developed three different classifications of the form of ...
References
External links
{{Deficiencies of intracellular signaling peptides and proteins
Disturbances of human pigmentation
Syndromes