Olfactory gene profiling in ticks: A scoping review with a functional perspective.

Area of Science:

• Zoology
• Genomics
• Molecular Biology

Background:

• Olfaction is crucial for tick host-seeking and mating behaviors, enabling detection of volatile chemical compounds.
• Understanding tick olfactory mechanisms is vital for controlling tick populations and preventing tick-borne diseases.

Purpose of the Study:

• To systematically map and synthesize literature on tick olfactory gene families.
• To examine the application of functional genomics and behavioral approaches in tick olfaction research.

Main Methods:

• A comprehensive literature search was conducted across five databases up to September 19, 2025.
• The scoping review followed the PRISMA-ScR guidelines, including 15 studies covering 12 tick species.
• Molecular methods like RNA sequencing and RT-qPCR were predominantly used to identify olfactory genes.

Main Results:

• Ten olfactory gene families were identified across 12 tick species, with Niemann-Pick type C2 proteins being most frequent (n=11).
• Gustatory receptor and ionotropic receptor families were also frequently identified (n=7).
• Significant differences in gene family distribution were observed among tick species, with *Haemaphysalis longicornis* and *Ixodes scapularis* showing the most identified olfactory genes.

Conclusions:

• This review highlights substantial progress in understanding tick olfaction at the molecular level.
• Further research utilizing functional validation techniques is essential for a comprehensive understanding.
• Advancing knowledge of tick olfaction can lead to targeted, olfaction-driven strategies for tick control and disease prevention.