Females are more commonly affected than males, and it becomes increasingly common with age. Signs and symptoms
RLS sensations range from pain or an aching in the muscles, to "an itch you cant scratch", a "buzzing sensation", an unpleasant "tickle that wont stop", a "crawling" feeling, or limbs jerking while awake. The sensations typically begin or intensify during quiet wakefulness, such as when relaxing, reading, studying, or trying to sleep.It is a "spectrum" disease with some people experiencing only a minor annoyance and others having major disruption of sleep and impairments in quality of life.The sensations—and the need to move—may return immediately after ceasing movement or at a later time. RLS may start at any age, including childhood, and is a progressive disease for some, while the symptoms may remit in others. In a survey among members of the Restless Legs Syndrome Foundation, it was found that up to 45% of patients had their first symptoms before the age of 20 years. "An urge to move, usually due to uncomfortable sensations that occur primarily in the legs, but occasionally in the arms or elsewhere. "The sensations are unusual and unlike other common sensations. Those with RLS have a hard time describing them, using words or phrases such as uncomfortable, painful, antsy, electrical, creeping, itching, pins and needles, pulling, crawling, buzzing, and numbness. It is sometimes described similar to a limb falling asleep or an exaggerated sense of positional awareness of the affected area.
Nijmegen breakage syndrome (NBS) is a rare autosomal recessive congenital disorder causing chromosomal instability, probably as a result of a defect in the double Holliday junction DNA repair mechanism and/or the synthesis dependent strand annealing mechanism for repairing double strand breaks in DNA (see Homologous recombination).NBS1 codes for a protein (nibrin) that has two major functions: (1) to stop the cell cycle in the S phase, when there are errors in the cell DNA (2) to interact with FANCD2 that can activate the BRCA1/BRCA2 pathway of DNA repair. This explains why mutations in the NBS1 gene lead to higher levels of cancer (see Fanconi anemia, Cockayne syndrome.) The name derives from the Dutch city Nijmegen, where the condition was first described.Most people with NBS have West Slavic origins. The largest number of them live in Poland. Presentation
It is characterized by microcephaly, a distinct facial appearance, short stature, immunodeficiency, radiation sensitivity and a strong predisposition to lymphoid malignancy. NBS is caused by a mutation in the NBS1 gene. Unsurprisingly, many of the features are similar to ataxia telangiectasia (AT) and this syndrome was sometimes termed AT-variant 1, as the protein mutated in AT, ATM, interacts with the MRE11/RAD50/NBS1 (MRN) complex. Other syndromes with clinical features similar to Nijmegen Breakage Syndrome include RAD50 deficiency and Cernunnos/NHEJ deficiency. Cause
NBS is caused by a mutation in the NBS1 gene, located at human chromosome 8q21. The disease is inherited in an autosomal recessive manner.