Advanced sleep phase syndrome
| Advanced sleep phase syndrome | |
| ICD-9 | 327.32 |
|---|---|
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1]
Overview
Advanced sleep phase syndrome (ASPS) is a sleep disorder in which patients feel very sleepy early in the evening (e.g. 18:00-19:00) and wake up very early in the night (e.g. midnight, 1:00, etc.). It is the opposite of delayed sleep phase syndrome. ASPS is frequently encountered in the elderly and in post-menopausal women. It can be treated pharmacologically, with evening bright lights, or behaviorally with chronotherapy or free-running sleep.
Familial Advanced Sleep Phase Syndrome (FASPS)
In 1999, Louis Ptáček’s research group at the University of California, San Francisco reported findings of a human circadian rhythm disorder showing a familial tendency. The disorder was characterized by a life-long pattern of sleep onset around 7:30pm and offset around 4:30am. Among three lineages, 29 people were identified as affected with this familial advanced sleep-phase syndrome (FASPS), and 46 were considered unaffected. The pedigrees demonstrated FASPS to be a highly penetrant, autosomal dominant trait.[1]
Two years after reporting the finding of FASPS, Ptáček’s group published results of genetic sequencing analysis on a family with FASPS. To narrow their search they took a cue from research on Per mutations in Drosophila[2] and mouse[3] models, which produced short-day mutants and were predicted to produce a phase advance in humans.[4] With this guidance they quickly found what they were looking for. Sequencing of the hPer2 gene revealed a serine-to-glycine point mutation in the CK1ε binding domain of the hPER2 protein.[5]
In 2005, Ptáček’s lab reported discovery of a different mutation causing FASPS. This time the CK1δ was implicated, demonstrating an A-to-G missense mutation that resulted in a threonine-to-alanine alteration in the protein.[6] The evidence for both of these reported causes of FASPS is strengthened by the absence of said mutations in all tested control subjects.[5][6]
Related Chapters
References
- ↑ Jones, Christopher R. (September 1999). "Familial advanced sleep-phase syndrome: A short-period circadian rhythm variant in humans". Nature Medicine. 5 (9): 1062–1065. doi:10.1038/12502. PMID 10470086. Retrieved 6 May 2007. Unknown parameter
|coauthors=ignored (help) - ↑ Konopka, Ronald J. (September 1971). "Clock mutants of Drosophila melanogaster". Proceedings of the National Academy of Sciences. 68 (9): 2112–2116. PMID 5002428. Retrieved 6 May 2007. Unknown parameter
|coauthors=ignored (help) - ↑ Zehng, Binhai (8 July 1999). "The mPer2 gene encodes a functional component of the mammalian circadian clock". Nature. 400 (6740): 169–173. doi:10.1038/22118. PMID 10408444. Retrieved 6 May 2007. Unknown parameter
|coauthors=ignored (help) - ↑ Klerman, E. B. (January 1996). "Simulations of light effects on the human circadian pacemaker: implications for assessment of intrinsic period". American Journal of Physiology. 270 (1): 271–282. PMID 8769811. Retrieved 6 May 2007. Unknown parameter
|coauthors=ignored (help) - ↑ 5.0 5.1 Toh, Kong L. (9 February 2001). "An hPer2 phosphorylation site mutation in familial advanced sleep phase syndrome". Science. 291 (5506): 1040–1043. doi:10.1126/science.1057499. PMID 11232563. Retrieved 6 May 2007. Unknown parameter
|coauthors=ignored (help) - ↑ 6.0 6.1 Xu, Ying (31 March 2005). "Functional consequences of a CKIδ mutation causing familial advanced sleep phase syndrome". Nature. 434 (7033): 640–644. doi:10.1038/nature03453. PMID 15800623. Retrieved 6 May 2007. Unknown parameter
|coauthors=ignored (help)