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22q13 deletion syndrome (spoken as ''twenty-two q one three''〔Technically, it should be spoken as ''twenty-two q one three''〕) is a genetic disorder caused by deletions or rearrangements on the q terminal end (long arm) of chromosome 22. Any abnormal genetic variation in the q13 region that presents with significant manifestations (phenotype) typical of a terminal deletion should be diagnosed as 22q13 deletion syndrome. 22q13 deletion syndrome is often placed in the more general category of Phelan-McDermid Syndrome (abbreviated PMS), which includes some mutations and microdeletions. The PMS name is less precise, since there is disagreement among researchers as to which variants belong in the PMS category. The Developmental Synaptopathies Consortium defines PMS as being caused by SHANK3 mutations, a definition that excludes terminal deletions. 〔 https://www.rarediseasesnetwork.org/cms/dsc/About-Us (downloaded 21-September-2015) 〕 A prototypical terminal deletion of 22q13 can be uncovered by karyotype analysis, but many terminal and interstitial deletions are too small. The availability of DNA microarray technology for revealing multiple genetic problems simultaneously has been the diagnostic tool of choice. The falling cost for whole exome sequencing and, eventually, whole genome sequencing, may replace DNA microarray technology for candidate evaluation. However, fluorescence in situ hybridization (FISH) tests remain valuable for diagnosing cases of mosaicism (mosaic genetics) and chromosomal rearrangements (e.g., ring chromosome, unbalanced chromosomal translocation). Although early researchers sought a monogenic (single gene genetic disorder) explanation, recent studies have not supported that hypothesis (see Etiology, below). 22q13 deletion syndrome is characterized by global developmental delay, absent or severely delayed speech, and neonatal hypotonia. There are approximately 1300 diagnosed cases of 22q13 deletion syndrome worldwide. ==Characteristics== The core characteristics of 22q13 Deletion syndrome (listed above) have a major impact on the individual. However, in addition to these characteristics, there are other manifestations than may range from mild to severe: Physical * Absent to severely delayed speech: 99% * Normal to accelerated growth: 95% * High tolerance to pain: 77% * Hypotonia (poor muscle tone): 75% * Dysplastic toenails: 73% * Long eyelashes: 73% * Poor thermoregulation: 68% * Prominent, poorly formed ears: 65% * Large or fleshy hands: 63% * Pointed chin: 62% * Dolichocephaly (elongated head): 57% * Ptosis (eyelid) (droopy eyelids): 57% * Gastroesophageal reflux: 42% * Epileptic seizures: 27% * Kidney problems: 26% * Delayed ability to walk: 18% Behavioral * Chewing on non food items: 85% * Delayed or unreliable toileting: 76% * Impulsive behaviors: 47% * Biting (self or others): 46% * Problems sleeping: 46% * Hair pulling: 41% * Autistic behaviors: 31% * Episodes of non-stop crying before age 5: 30% * Teeth grinding: (unknown) % 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「22q13 deletion syndrome」の詳細全文を読む スポンサード リンク
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