The phrase "affecting a large fraction" is correct and usable in written English.
It can be used when discussing the impact or influence of something on a significant portion of a population or group.
Example: "The new policy is affecting a large fraction of the workforce, leading to widespread changes in job roles."
Alternatives: "impacting a significant portion" or "influencing a large segment".
We propose a research agenda to fill knowledge gaps and catalyze a conversation about an approach to wildlife management that affects a large fraction of public and private land.
Directly transferred to a road situation, these results indicate that salt in much smaller amounts than what is currently used could weaken snow considerably, provided that the solution is sufficiently distributed to affect a large fraction of the grain bonds.
Induction of APECs is rapid and affects a large fraction of cells.
Both diseases affect a large fraction of the world population, with prostate cancer affecting one in six men, and CFS affecting an estimated 0.4 to 1% of the population.
The analysis combined a number of data sets to show that compliance with a range of alternative annual and 24-hr PM2.5 standard groupings would affect a large fraction of the total population in the Northeast.
It has been shown previously that exposure through incorporation of contaminated food potentially affects a large fraction of the population and poses the most relevant radiological risks once evacuation measures have been completed.
"The Knowledge Graph features affect a larger fraction of queries than Universal Search.
Within each genome compartment, weak selection affects a larger fraction of indels than of SNPs, and, among indels, a larger fraction of deletions than of insertions.
From left to right (total, urban, agricultural part of the catchment) the exposure profiles affect a larger fraction of combinations of species and effect type and more severe effects are seen earlier.
Therefore, although not quantitatively impacting the overall mRNA levels substantially, NMD affects qualitatively a large fraction of the mRNA transcription units.
