Garcia-Heras Jaime, Martin Judith
Genetic Testing Center, Bureau of Laboratories, Texas Department of Health, Denton, Texas, USA.
Am J Med Genet. 2002 May 1;109(3):226-30. doi: 10.1002/ajmg.10353.
A rec(4) dup 4p inherited from a maternal inv(4)(p15q35) was detected in a four-year-old girl with malformations, developmental delay, and behavioral problems that resemble those for trisomy 4p. A review of eight other liveborns with rec(4) dup 4p shows that about 40% of them also have manifestations in common with trisomy 4p, but the rest have a variable spectrum of malformations. Overall, the rec(4) dup 4p phenotype is not specific, and a diagnosis would not have been feasible without cytogenetic studies. This lack of a clinically recognizable phenotype could reflect the effects of the variable sizes of deletions of 4q, molecular differences in the break points, or the known variable expression of trisomy 4p. The fact that 79% of the recombinants in the offspring of inv(4)(p13-p15q35) carriers are rec(4) dup 4p suggests that meiotic recombination favors its generation or that rec(4) dup 4q are more lethal in utero.
在一名患有畸形、发育迟缓及行为问题（类似于4p三体综合征）的4岁女童中，检测到从母亲的inv(4)(p15q35)遗传而来的rec(4) dup 4p。对其他8例活产rec(4) dup 4p患者的回顾显示，其中约40%也有与4p三体综合征相同的表现，但其余患者有一系列不同的畸形。总体而言，rec(4) dup 4p的表型并不特异，若无细胞遗传学研究，诊断是不可行的。这种缺乏临床可识别表型的情况可能反映了4q缺失大小的变化、断点处的分子差异或已知的4p三体综合征可变表达的影响。inv(4)(p13 - p15q35)携带者后代中79%的重组体是rec(4) dup 4p这一事实表明，减数分裂重组有利于其产生，或者rec(4) dup 4q在子宫内更具致死性。
