我在文献中看到有人根据TCGA数据分析了肾细胞癌的测序信息，得出了3号染色体拷贝数下降的结果。请问这种结果是怎么得出的呢？谢谢老师。
附文献中的原文：doi:10.1038/modpathol.2017.72
“An
additional 143 were found to have a 3p arm copy
number loss without detection of VHL mutation or
deep deletion. Another 20 were found to have
decreased copy number for the entire chromosome
3, interpreted as monosomy 3.
”