Seckel syndrome
Seckel syndrome | |
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Other names: Harper's syndrome | |
Specialty | Medical genetics |
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 an extremely rare congenital nanosomic disorder. Inheritance is autosomal recessive.[2] It is characterized by intrauterine growth restriction and postnatal dwarfism with a small head, narrow bird-like face with a beak-like nose, large eyes with down-slanting palpebral fissures,[3] receding mandible and intellectual disability.
A mouse model has been developed.[4] This mouse model is characterized by a severe deficiency of ATR protein.[4] These mice suffer high levels of replicative stress and DNA damage. Adult Seckel mice display accelerated ageing.[4] These findings are consistent with the DNA damage theory of aging.
Symptoms and signs
Symptoms include:
- Intellectual disability (more than half of the patients have an IQ below 50)
- Microcephaly
- Sometimes pancytopenia (low blood counts)
- Cryptorchidism
- Low birth weight
- Dislocations of pelvis and elbow
- Unusually large eyes
- Low ears
- Small chin
- Cleft palate (unusual)
Genetics
It is believed 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:
Type | OMIM | Gene | Locus |
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SCKL1 | 210600 | ATR | 3q22-q24 |
SCKL2 | 606744 | ? | 18p11-q11 |
SCKL3 | 608664 | ? | 14q |
SCKL4 | 613676 | CENPJ | 13q12 |
Diagnosis
Differential diagnosis
The DDX with microcephalic osteodysplastic dwarfism type II is done via radiographic survey [5]
Treatment
Management of intellectual disability of affected individual will be needed. Hematological abnormalities will need medical management also[5]
History
The syndrome was named after German- American physician Helmut Paul George Seckel[6] (1900–1960). The synonym Harper's syndrome was named after Rita G. Harper.[7][8]
See also
- Koo-Koo the Bird Girl
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. Archived from the original on 2021-03-05. Retrieved 2021-01-28.
- ↑ 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. Archived from the original on 2 January 2022. Retrieved 7 January 2011.
- ↑ Jung M, Rai A, Wang L, Puttmann K, Kukreja K, Koh CJ (2018). "Nephrolithiasis in a 17-Year-Old Male With Seckel Syndrome and Horseshoe Kidneys: Case Report and Review of the Literature". Urology. 120: 241–243. doi:10.1016/j.urology.2018.05.023. PMID 29894776.
- 1 2 3 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.
- 1 2 RESERVED, INSERM US14-- ALL RIGHTS. "Orphanet: Seckel syndrome". www.orpha.net. Archived from the original on 20 January 2021. Retrieved 12 August 2021.
- ↑ Seckel, H. P. G. Bird-headed Dwarfs: Studies in Developmental Anthropology Including Human Proportions. Springfield, Ill.: Charles C Thomas (pub.) 1960.
- ↑ "Seckel's syndrome". Archived from the original on 2021-01-28. Retrieved 2021-01-28.
- ↑ 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.
External links
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