For PGD-AS, CGH is an attractive method as it displays all the chromosomes at the same time. Although single-cell CGH has been applied on early embryos for research purposes,[16,17] its clinical application is not straightforward. All present CGH protocols have a time requirement of 4 to 5 days that is impossible to fit into the PGD situation with biopsies at day 3 and embryo transfer on day 4 or 5. However, one group has reported the use of CGH in PGD-AS, resulting in the birth of a healthy baby. The obstacle was overcome by cryopreservation of the embryos after biopsy while awaiting the results. Alternatively, an accelerated protocol with polar body biopsy at day 1 could be used.
The main disadvantage of CGH is that it is labor intensive and demands the knowledge of karyotyping. In microarray-CGH the target for hybridization are arrays of genomic clones spotted to glass slides. This setting allows for automation as well as improved resolution, down to 100-200 kb depending on the number and density of clones present on the slide, compared to 2-20 Mb for conventional CGH. The use of microarrays in PGD for monogenic disorders will probably have a limited value because in most cases only one or two mutations have to be identified.
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The use of dumbbells gives you a much more comprehensive strengthening effect because the workout engages your stabilizer muscles, in addition to the muscle you may be pin-pointing. Without all of the belts and artificial stabilizers of a machine, you also engage your core muscles, which are your body's natural stabilizers.