|Classification and external resources|
|MeSH||C537533, C537534, C563881|
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) is an extremely rare congenital nanosomic disorder.
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 down-slanting palpebral fissures, receding mandible and intellectual disability.
A mouse model has been developed. This mouse model is characterized by a severe deficiency of ATR protein. These mice suffer high levels of replicative stress and DNA damage. Adult Seckel mice display accelerated aging. These findings are consistent with the DNA damage theory of aging.
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.
- intellectual disability (more than half of the patients have an IQ below 50)
- sometimes pancytopenia (low blood counts)
- low birth weight
- dislocations of pelvis and elbow
- unusually large eyes
- low ears
- small chin
- 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.
- James Wynbrandt; Mark D. Ludman (February 2008). The encyclopedia of genetic disorders and birth defects. Infobase Publishing. pp. 344–. ISBN 978-0-8160-6396-3. 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. PMC . PMID 19620979. doi:10.1038/ng.420.
- Seckel, H. P. G. Bird-headed Dwarfs: Studies in Developmental Anthropology Including Human Proportions. Springfield, Ill.: Charles C Thomas (pub.) 1960.
- 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. PMID 6022184. doi:10.1016/S0022-3476(67)80334-2.