Turner A M, Robinson H, Wake S, Laing S J, Leigh D, Turner G
Fragile X Department, Prince of Wales Hospital, Randwick, N.S.W., Australia.
Am J Med Genet. 1994 Jul 15;51(4):458-62. doi: 10.1002/ajmg.1320510432.
We have derived risk figures for fra(X) syndrome carrier mothers based on their DNA status. Clinical and molecular information was analysed in 200 carrier mothers and their offspring. Individuals were classified as affected by a requirement for special education. Risk figures were calculated using the genotype of the intellectually normal offspring in order to reduce ascertainment bias. Analysis was made on women with differing mutation size to predict the proportion of affected offspring. Using this method the following risk figures were derived: 1. For carrier women with an increase (delta) of 0.06-0.14 Kb, the risk for having an affected son was 29% (1 in 3.5) and 25% for daughters (1 in 4). This predicts an overall 73% chance of a normal child. 2. For delta size 0.15-0.24 Kb, the risk of having an affected son was 46% (1 in 2.2) and 32% for daughters (1 in 3.1), predicting a 61% chance of a normal child. 3. For delta size > 0.24 Kb, normal transmitting male offspring were not seen, i.e., the risk for males was 50% (1 in 2) and for females 32% (1 in 3.1) which predicts a 59% chance of a normal child.
我们根据DNA状态得出了脆性X综合征携带者母亲的风险数据。对200名携带者母亲及其后代的临床和分子信息进行了分析。根据接受特殊教育的需求将个体分类为受影响者。为减少确诊偏倚，使用智力正常后代的基因型计算风险数据。对不同突变大小的女性进行分析，以预测受影响后代的比例。采用这种方法得出了以下风险数据：1. 对于增加（δ）0.06 - 0.14 Kb的携带者女性，生育患病儿子的风险为29%（1/3.5），女儿为25%（1/4）。这预测正常孩子的总体概率为73%。2. 对于δ大小为0.15 - 0.24 Kb的情况，生育患病儿子的风险为46%（1/2.2），女儿为32%（1/3.1），预测正常孩子的概率为61%。3. 对于δ大小> 0.24 Kb的情况，未观察到正常传递的男性后代，即男性风险为50%（1/2），女性为32%（1/3.1），这预测正常孩子的概率为59%。
