[Establishment of lymphocyte cell lines with abnormal chromosome karyotypes and its application in external quality assesment for chromosome karyotype analysis].

Objective: To develop chromosome abnormal karyotype quality control cell and to explore the external quality assessment (EQA) method for chromosome karyotype analysis.

Methods: The chromosome abnormal karyotype quality control cells were prepared by EB virus (EBV) transfection of human B lymphocyte strain establishment and were distributed to participating labs for EQA test of chromosome karyotype analysis project at appointed time. The evaluation results were obtained through 4 grades scoring.

Results: Six kinds of chromosome abnormal karyotype quality control cells were initially developed, the karyotypes of which were 46,X, t(Y;5)(q12;q21), 46, XY, 15p +, 46, XX, t(13;18)(q12;q21), 46, X, r(Xp), 46,X,t(Y;Y), 46,XX,t(9;20)(p13;p13) respectively. In the external quality assessment, feedbacks from the participating labs on the sequencing results of the six kinds of quality control cells showed that the wholly overlapping rate were 82.1%, 92.0%, 84.6%, 80.8%, 86.2%, 74.1% and the wholly deviation rate were 10.7%, 8.0%, 11.5%, 19.2%, 13.8%, 18.5%. The overall wholly overlapping rate, partial overlapping rate, partial deviation rate and wholly deviation rate turned out to be 83.2%, 0.6%, 2.5% and 13.7% respectively.

Conclusion: The misdiagnose rate of chromosome karyotype analysis is rather high and regular external quality assessment is necessary to achieve dynamic information and improve diagnosis quality.