The single cell as a tool for genetic testing: credibility, precision, implication.
OBJECTIVE
To investigate the influence of amplicons size and cell type on allele dropout and amplification failures in single-cell based molecular diagnosis.


METHODS
730 single lymphocytes and amniotic cells were collected from known heterozygotes individuals to one of the common Ashkenazi Jewish mutations: 1278+TATC and IVS12+1G>C which cause Tay Sachs Disease, IVS20+6T and 854A>C which underlie Familial Dysautonomia and Canavan Disease. DNA was extracted and analyzed by our routine methods.


RESULTS
Reduced rates of allele dropout and amplification failure were found when smaller amplification product were designed and in amniotic cultured cells compared to peripheral lymphocytes. Cultured lymphocytes, induced to divide, demonstrated significantly less allele dropout than non induced lymphocytes suggesting the role of division potential on amplification efficiency.


CONCLUSIONS
Single cell based diagnosis should be designed for each mutation. Minimal sized amplicons and cell having division potential should be preferred, as well as sensitive techniques to detect preferential amplification.
Dotan
Keren
K
Danek Gertner Institute of Human Genetics, Sheba Medical Center, Tel-Hashomer, Ramat Gan, 52621, Israel.
Feldman
Baruch
B
Goldman
Boleslaw
B
Peri
Yehuda
Y
Peleg
Leah
L
D000653:Amniotic Fluid / Q000166:cytology; D017825:Canavan Disease / Q000235:genetics; D004252:DNA Mutational Analysis; D004402:Dysautonomia, Familial / Q000235:genetics; D006801:Humans; D008214:Lymphocytes; D021141:Nucleic Acid Amplification Techniques; D019836:Preimplantation Diagnosis / Q000379:methods*; D012680:Sensitivity and Specificity; D013661:Tay-Sachs Disease / Q000235:genetics