While one can efficiently isolate conditional, embryonic-lethal C. elegans mutants, positional cloning of the mutant loci has remained laborious and time consuming, substantially limiting the utility of mutant screens, particularly given how readily one can use RNA interference to probe essential C. elegans gene functions [6], [28], [29], [30], [31], [32].
In Drosophila, this powerful technique has remained laborious and hence seldom implemented.
However, the genotyping processes that are based on PCR markers remain laborious, expensive, and time-consuming.
To date, direct experimental methods for typing HLA genes (via serology or PCR) remain laborious, expensive, and time consuming.
Although C. elegans offers the fastest transgenesis of any animal model, manual injections remain laborious and low throughput, and thus are not amenable to the kind of large-scale screening applications available for bacteria, yeast, or tissue culture.
However, establishing which of the observed mutations contribute to the selected phenotype still remained a laborious process, in which mutations have to be reversed engineered in a naive strain, either individually or in combination.
However performing MLST remains laborious and expensive.
Finally, as has previously been recognized without either better databases of venom protein sequences or facile and rapid de novo sequencing technologies for mass spectrometry, snake venom proteome investigation will remain a laborious task.
Despite these successes, the process of positional cloning, i.e. the identification of the gene and variant(s) that causes the phenotype has remained a challenging and laborious process.
The laborious process of categorizing the cucumbers had remained essentially the same for decades, until last spring, when Koike began developing a new approach.
Although MLST has become the standard method to study the population structure of GBS [ 22, 24], more rapid and less expensive and laborious methods remain useful for carrying out single centre studies.
