Etiological Analysis of Neurodevelopmental Disabilities: Single-Center Eight-Year Clinical Experience in South China

Figure 5

Chromosome abberation in a 6-year-old female with mental retardation (MR). High-resolution GTG-banding in Figure 5(a) revealed the derivative chromosomes 7 and 9 (question mark), and their detailed identities were further illustrated by the results of FISH analysis. Figure 5(b) showed four red signals in a metaphase, by means of utilization of whole chromosome 7 painting probe (WCP 7, red). The normal chromosome 7 had one intact red signal, but the derivative chromosome 7 (arrow) had two dispersed red signals, and a fragment of chromosome 7(arrowhead) was inserted into a chromosome 9, forming a derivative chromosome 9. Similarly, FISH analysis with WCP 9 (red) in Figure 5(c) showed the normal chromosome 9 with intact red signal, the derivative chromosome 9 (arrow) with two dispersed red signals, and the derivative chromosome 7 with a inserted fragment of chromosome 9 (arrowhead). Finally, the chromosome karyotype in this patient was identified as 46, XX, ins (7;9) (p13; q32q22) inv(7) (p11.2 q11.23), ins (9;7) (q22; q22q32), ish ins(7;9) (WCP7+, WCP9+), ins(9;7) (WCP7+,WCP9+).