The phrase "a large fraction of unknown" is not correct in standard written English.
It may be intended to refer to a significant portion of something that is not known, but it lacks clarity and specificity.
Example: "In our research, we found that a large fraction of unknown variables could affect the outcome of the experiment."
Alternatives: "a significant portion of unknown" or "a considerable amount of unknown".
The causes of a large fraction of stillbirths remain unknown, even when extensive testing and autopsy are performed [ 7- 11].
Modules 5 and 7 contain both a large fraction of genes with unknown functions and groups of genes with significantly enriched common functions or common TFs.
The approaches that have been used mainly concern the genes in outcome classifiers (typically below 100 genes) often including a large fraction of genes with unknown function.
It is interesting to note that there is still a large fraction of peptides with unknown structure (∼39%) being comparable to the fraction of peptides with α-helical structure (∼34%), which seems to be the predominant one.
In all sequenced genomes, a large fraction of predicted genes encodes proteins of unknown biochemical function and up to 15% of the genes with "known" function are mis-annotated.
Since a large fraction of proteins are hypothetical or of unknown function, we added for each species a second row which exclusively depicts those with an associated function.
Importantly, no candidate genes involved in BA biosynthesis could be identified, however, as the genes involved in this process are largely unknown and a large fraction of the genes differentially expressed in corollas of ir- hd20 are of undescribed function (supplementary file 5), it is plausible that among these genes some involved in BA biosynthesis are present.
We used viral metagenomes because they are more challenging than microbial metagenomes because of the high diversity and large fraction of unknown sequences.
In addition, given the large fraction of unknown chemical reactions in biological systems and the immense space of macromolecules potentially catalyzing chemical reactions (Dobson, 2004), the most promising targets for metabolic engineering may not be found among the already characterized enzymes.
The physiologic function of a large fraction of these 800 GPCRs is unknown.
