Original articleThe movement disorders of Coffin–Lowry syndrome☆
Section snippets
Background
Coffin–Lowry syndrome (CLS) is an X-linked semi-dominant condition with dysmorphism and cognitive difficulties, more severe in affected males, due to mutations in the RSK2 protein kinase gene. The expression of this RSK2 gene has been mapped in human and mouse brain and reported to be prominently expressed in brain structures essential for cognition and learning [1]. It has recently become clear that an important neurological complication of CLS is some form of drop attack, beginning on
Clinical observations
We have made some further clinical observations and video recordings on two further individuals with CLS known to us.
Epidemiological observations
One of us (MH) started the Coffin–Lowry syndrome Foundation (CLSF) as a support group in 1991 after her son was diagnosed with CLS. Families of those diagnosed as CLS by a physician or geneticist make contact via the web site. Of 265 affected individuals on the CLSF database, 8 have a confirmed RSK2 defect, 5 do not, and the remainder have a clinical diagnosis of CLS.
Table 3 gives the age distribution of those on the database with known age, both with and without a history of drop attacks. From
Discussion and future proposals
The mechanisms of the movement disorders of Coffin–Lowry syndrome have been controversial. It seems that there are four reasons for this. One is that the movement disorder varies from individual to individual, so that one may have something more like cataplexy and another something more like hyperekplexia (Table 1). Secondly, more than one movement disorder may be present in the same individual with CLS [11], [13] as in the patient in Case 2 in the present paper. Thirdly, the movement disorder
Acknowledgements
We thank the families for permission to report clinical details and to include the photographs shown in the figures. Thanks to Dr R. Holden for referring the patient in Case 2 to the first author. Alastair Irwin, Chief of Medical Illustration, Yorkhill Hospitals, Glasgow kindly prepared the figures. The web site for the Home Page of the Coffin–Lowry Syndrome Foundation is http://www.clsf.info/.
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2012, European Journal of Medical GeneticsCitation Excerpt :The overall prevalence is approximately 10–14% [5]. Data from the CLS Foundation’s database revealed a higher overall prevalence of 20% and a peak prevalence of 21–27% between ages of 10–20 [10]. It should be mentioned that, although the majority of reported cases with SIDEs appear to be male, about one-third are female cases (7/22) [4,8–12].
Four novel RSK2 mutations in females with Coffin-Lowry syndrome
2010, European Journal of Medical GeneticsNarcolepsy in childhood
2009, Sleep Medicine ReviewsCitation Excerpt :In such cases, Niemann–Pick disease, type C should be excluded or verified by specific enzymatic examination, and NPC1 mutation by molecular genetic examination could be proved. Sudden drop attacks resembling cataplexy-like events should draw attention to the Coffin–Lowry syndrome.69,70 Generally speaking, a high rate of cataplectic attacks, HLA negativity and detectable CSF Hcrt-1 level increase the probability of symptomatic cases.
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The paper is based on the lecture given at the sixth annual meeting of the Infantile Seizure Society, Tokyo, March 15–16, 2003.