Trabalza N, Furbetta M, Rosi G, Donti E, Venti G, Migliorini Bruschelli G
J Genet Hum. 1978 Jun;26(2):177-84.
The authors report the case of a 2-month-old infant with psychomotor retardation and several physical stigmata. Cytogenetic studies of the patient using the normal technique show in all the cells a karyotype 46,XY with a G group chromosome substituted by an F-like mediocentric element with satellites. The R, G and C-banding methods reveal that it is the 22 with too developed short arms (22p+). This element was found in the mother's and maternal grandfather's karyotypes although they both present normal phenotypes. The authors advance two hypotheses concerning the origin of the alteration but cannot exclude a possible connection between this particular chromosome and the proband's anomalies. The difficulties of genetic counselling in this case are evident.
作者报告了一例患有精神运动发育迟缓及多种身体特征的2个月大婴儿的病例。采用常规技术对该患者进行细胞遗传学研究，结果显示所有细胞的核型为46,XY，其中一条G组染色体被一条带有随体的类F中着丝粒元件所替代。R、G和C显带方法显示，该染色体是短臂过度发育的22号染色体（22p+）。尽管母亲及其外祖父的表型均正常，但在他们的核型中也发现了这一元件。作者提出了关于这种变异起源的两种假说，但无法排除这条特殊染色体与先证者异常之间可能存在的联系。在这种情况下，遗传咨询的困难显而易见。
