Miller K, Reimer A, Schulze B
Abteilung Humangenetik, Medizinischen Hochschule Hannover, FRG.
Ann Genet. 1987;30(3):180-2.
A direct tandem duplication chromosome 21 was found in a boy with Down's syndrome. The proband's mother and grandmother both carried a ring chromosome 21. The observed duplication chromosome in the child may be explained either by recombination between the maternal ring and the mother's normal chromosome 21 or by break of a double-sized ring chromosome 21.
在一名唐氏综合征男孩中发现了一条21号染色体直接串联重复。先证者的母亲和祖母都携带一条21号环状染色体。孩子中观察到的重复染色体可以通过母源环状染色体与母亲正常21号染色体之间的重组，或者通过一条双倍大小的21号环状染色体断裂来解释。
