# How do I validate a single sample ArrayCGH result?

We have arrayCGH (aCGH) results for one sample. There is a 0.5 Mb terminal duplication on chromosome 19 (62995490-63407936, according to NCBI36/hg18). The duplication is rare: a literature review suggests there are only 3-4 samples with clinical information.

What are the steps to validate the results? How do we ascertain that this duplication is the cause of the clinical symptoms?

I have some ideas:

• aCGH the parents. Not sure how this would help.
• whole genome exome sequencing. Worried this might make it more difficult to pinpoint genetic cause.
• whole genome sequencing?
• other ideas?

Note: I am new to aCGH and high-throughput sequencing, any advice is welcome.

• Is the duplication in the telomere or before it? May 31 '17 at 21:15
• @DevonRyan I think, it is before, on the last band of chr19. Does it matter, sorry not being ignorant, just no clue about it. May 31 '17 at 21:25
• Telomeric sequences are highly repetitive, so yes it matters :) May 31 '17 at 21:26
• Telomere starts at the end of the last band, or is it part of chromosome? May 31 '17 at 21:28
• If you look at the UCSC genome browser, the telomere is the GGGTTA simple repeat at the end. In others it's just a stretch of NNNN in the reference (no clue how this looks in hg18). May 31 '17 at 21:43