Upadhyaya M, Lunt P W, Sarfarazi M, Broadhead W, Daniels J, Owen M, Harper P S
Institute of Medical Genetics, University of Wales College of Medicine, Cardiff.
J Med Genet. 1991 Oct;28(10):665-71. doi: 10.1136/jmg.28.10.665.
Close linkage of a hypervariable DNA probe on chromosome 4q (pH30, locus D4S139) has been found with the locus for facioscapulohumeral disease. Three recombinants were identified in a total of 140 meioses, giving a maximum lod score of 36.77 at a recombination fraction of 0.02. All but two of the families studied proved informative with this probe; all informative families showed evidence of linkage (except one family with a single scorable meiosis), making genetic heterogeneity unlikely from our data. The close linkage and highly informative nature of the probe will make it suitable for clinical application in presymptomatic and prenatal diagnosis. We have also confirmed loose linkage with the marker (Mfd22, locus D4S171) used to establish the initial assignment of the disorder to chromosome 4.
已发现位于4号染色体q臂上的一个高变DNA探针(pH30,基因座D4S139)与面肩肱型肌营养不良症的基因座紧密连锁。在总共140次减数分裂中鉴定出3个重组体,在重组率为0.02时,最大lod值为36.77。除两个研究家系外,其余所有家系对此探针均为信息家系;所有信息家系均显示出连锁证据(有一个家系只有一次可计分的减数分裂除外),根据我们的数据,不太可能存在遗传异质性。该探针的紧密连锁和高度信息性使其适用于症状前和产前诊断的临床应用。我们还证实了与用于将该疾病最初定位于4号染色体的标记(Mfd22,基因座D4S171)存在松散连锁。