Liehr T, Bartels I, Zoll B, Ewers E, Mrasek K, Kosyakova N, Merkas M, Hamid A B, von Eggeling F, Posorski N, Weise A
Jena University Hospital, Institute of Human Genetics, Kollegiengasse 10, Jena, Germany.
Cytogenet Genome Res. 2011;132(1-2):121-3. doi: 10.1159/000316393. Epub 2010 Jul 20.
Unbalanced chromosomal abnormalities (UBCA) are reported for >50 euchromatic regions of almost all human autosomes. UBCA are comprised of a few megabases of DNA, and carriers are in many cases clinically healthy. Here we report on a partial trisomy of chromosome 4 of the centromere-near region of the short arm of chromosome 4 present as a small supernumerary marker chromosome (sSMC). The sSMC was present in >70% of amnion cells and in 60% of placenta. Further delineation of the size of the duplicated region was done by molecular cytogenetics and array comparative genomic hybridization. Even though the sSMC lead to a partial trisomy of ~9 megabase pairs, a healthy child was born, developing normally at 1 year of age. No comparable cases are available in the literature. Thus, we discuss here the possibility of having found a yet unrecognized chromosomal region subject to UBCA.
几乎所有人类常染色体的50多个常染色质区域都报告存在染色体不平衡异常（UBCA）。UBCA由几百万碱基对的DNA组成，许多携带者在临床上是健康的。在此，我们报告一例4号染色体短臂着丝粒附近区域的部分三体，表现为一条小的额外标记染色体（sSMC）。该sSMC存在于70%以上的羊膜细胞和60%的胎盘中。通过分子细胞遗传学和阵列比较基因组杂交进一步确定了重复区域的大小。尽管该sSMC导致了约9兆碱基对的部分三体，但仍产下一名健康婴儿，其1岁时发育正常。文献中没有类似病例。因此，我们在此讨论发现一个尚未被认识的易发生UBCA的染色体区域的可能性。
