Shwachman syndrome as mutator phenotype responsible for myeloid dysplasia/neoplasia through karyotype instability and chromosomes 7 and 20 anomalies.
Synopsis
exocrine pancreatic insufficiency
short stature
bone marrow dysfunction
metaphyseal dysostosis
epiphyseal dysplasia
immune dysfunction
liver disease
growth failure
renal tubular defects
insulin-dependent diabetes mellitus
psychomotor retardation
hematological disorders
- neutropenia
- anemia
- raised fetal hemoglobin (HbF) levels
- thrombocytopenia
- impaired neutrophil chemotaxis
- aplastic anemia
- myelodysplastic syndrome (MDS)
- acute myeloid leukemia (AML)
Cytogenetics
i(7)(q10)
del(20)(q11)
The rate of chromosome breaks is not significantly higher than in controls, from which it is concluded that SS should not be considered a breakage syndrome (chromosomal breakage syndromes).
A specific kind of karyotype instability is present in SS, with chromosome changes possibly found in single cells or small clones, often affecting chromosomes 7 and 20, in the BM.
References
Maserati E, Minelli A, Pressato B, Valli R, Crescenzi B, Stefanelli M, Menna G, Sainati L, Poli F, Panarello C, Zecca M, Curto FL, Mecucci C, Danesino C, Pasquali F. Shwachman syndrome as mutator phenotype responsible for myeloid dysplasia/neoplasia through karyotype instability and chromosomes 7 and 20 anomalies. Genes Chromosomes Cancer. 2005 Dec 28; PMID: 16382447