The Seckel syndrome or microcephalic primordial dwarfism (also known as bird-headed dwarfism, Harper's syndrome, Virchow-Seckel dwarfism, and Bird-headed dwarf of Seckel[1]) is a congenital nanosomic disorder.
Inheritance is autosomal recessive.[2]
It is characterized by intrauterine growth retardation and postnatal dwarfism with a small head, narrow bird-like face with a beak-like nose, large eyes with an antimongoloid slant, receding mandible and mental retardation.
A mouse model has been developed.[3]
[edit] Genetics
It is supposed to be caused by defects of genes on chromosome 3 and 18. One form of Seckel syndrome can be caused by mutation in the gene encoding the ataxia telangiectasia and Rad3 related protein (ATR) which maps to chromosome 3q22.1-q24. This gene is central in the cell's DNA damage response and repair mechanism.
Types include:
[edit] History
The syndrome was named after Helmut Paul George Seckel[4] (American physician, 1900–1960). Harper's syndrome is named after Rita G. Harper.[5][6]
[edit] Symptoms
Symptoms include:
- mental retardation (more than half of the patients have an IQ below 50)
- microcephaly
- sometimes pancytopenia
- cryptorchidism
- low birth weight
- dislocations of pelvis and elbow
- unusually large eyes
- low ears
- small chin
[edit] External links
[edit] See also
[edit] References
- ^ Harsha Vardhan BG, Muthu MS, Saraswathi K, Koteeswaran D (2007). "Bird-headed dwarf of Seckel". J Indian Soc Pedod Prev Dent 25 Suppl: S8–9. PMID 17921644. http://www.jisppd.com/article.asp?issn=0970-4388;year=2007;volume=25;issue=5;spage=8;epage=9;aulast=Harsha.
- ^ James Wynbrandt; Mark D. Ludman (February 2008). The encyclopedia of genetic disorders and birth defects. Infobase Publishing. pp. 344–. ISBN 9780816063963. http://books.google.com/books?id=kXaMjwItP0oC&pg=PA344. Retrieved 7 January 2011.
- ^ Murga M, Bunting S, Montaña MF, et al. (August 2009). "A mouse model of ATR-Seckel shows embryonic replicative stress and accelerated aging". Nat. Genet. 41 (8): 891–8. doi:10.1038/ng.420. PMC 2902278. PMID 19620979. http://www.pubmedcentral.nih.gov/articlerender.fcgi?tool=pmcentrez&artid=2902278.
- ^ Seckel, H. P. G. Bird-headed Dwarfs: Studies in Developmental Anthropology Including Human Proportions. Springfield, Ill.: Charles C Thomas (pub.) 1960.
- ^ http://www.whonamedit.com/synd.cfm/869.html
- ^ Harper RG, Orti E, Baker RK (May 1967). "Bird-beaded dwarfs (Seckel's syndrome). A familial pattern of developmental, dental, skeletal, genital, and central nervous system anomalies". J. Pediatr. 70 (5): 799–804. doi:10.1016/S0022-3476(67)80334-2. PMID 6022184.
|
Deficiencies of intracellular signaling peptides and proteins
|
|
| GTP-binding protein regulators |
|
|
| G protein |
|
|
| MAP kinase |
|
|
| Other kinase/phosphatase |
|
|
| Signal transducing adaptor proteins |
|
|
| Other |
|
|
see also intracellular signaling peptides and proteins
B structural (perx, skel, cili, mito, nucl, sclr) · DNA/RNA/protein synthesis (drep, trfc, tscr, tltn) · membrane (icha, slcr, atpa, abct, othr) · transduction (iter, csrc, itra), trfk
|
|
|
Nucleus diseases
|
|
| Telomere |
|
|
| Nucleolus |
|
|
| Centromere |
CENPJ ( Seckel syndrome 4)
|
|
| Other |
|
|
see also nucleus
B structural (perx, skel, cili, mito, nucl, sclr) · DNA/RNA/protein synthesis (drep, trfc, tscr, tltn) · membrane (icha, slcr, atpa, abct, othr) · transduction (iter, csrc, itra), trfk
|
|
