Ohye Tamae, Inagaki Hidehito, Kato Takema, Tsutsumi Makiko, Kurahashi Hiroki
Division of Molecular Genetics, Institute for Comprehensive Medical Science, Fujita Health University, Toyoake, Aichi, Japan.
Pediatr Int. 2014 Aug;56(4):462-6. doi: 10.1111/ped.12437.
Constitutional t(11;22)(q23;q11) is the most frequent recurrent non-Robertsonian translocation in humans. Balanced carriers of t(11;22) usually manifest no clinical symptoms, and are often identified after the birth of offspring with an unbalanced form of this translocation, known as Emanuel syndrome. To determine the prevalence of the disorder, we sent surveillance questionnaires to 735 core hospitals in Japan. The observed number of Emanuel syndrome cases was 36 and that of t(11;22) balanced translocation carriers, 40. On the basis of the de novo t(11;22) translocation frequency in sperm from healthy men, we calculated the frequency of the translocations in the general population. Accordingly, the prevalence of Emanuel syndrome was estimated at 1 in 110,000. Based on this calculation, the estimated number of Emanuel syndrome cases in Japan is 1063 and of t(11;22) balanced translocation carriers, 16,604, which are much higher than the numbers calculated from the questionnaire responses. It is possible that this discordance is partly attributable to a lack of disease identification. Further efforts should be made to increase the awareness of Emanuel syndrome to ensure a better quality of life for affected patients and their families.
染色体组型t(11;22)(q23;q11)是人类中最常见的非罗伯逊易位。t(11;22)平衡携带者通常无临床症状，常在其后代出生后被诊断为这种易位的不平衡形式（即 Emanuel综合征）时才被发现。为了确定该疾病的患病率，我们向日本的735家核心医院发送了监测问卷。观察到的 Emanuel综合征病例数为36例，t(11;22)平衡易位携带者为40例。根据健康男性精子中新生t(11;22)易位频率，我们计算了普通人群中的易位频率。据此，Emanuel综合征的患病率估计为1/110,000。基于此计算，日本Emanuel综合征病例的估计数为1063例，t(11;22)平衡易位携带者为16,604例，这远高于根据问卷调查回复计算出的数字。这种差异可能部分归因于疾病识别不足。应进一步努力提高对Emanuel综合征的认识，以确保受影响患者及其家庭有更好的生活质量。
