The karyotype appears to an inversion of chromosome 9.Because the region of inversion only contains heterochromatin. It is usually of no clinical significance.

• 报告显示倒转区域在没有基因存在的异染色质区上，台湾人第九号染色体异染色质区倒转发生率约为1.；2%25，这些人并没有异常症状。