The posting
An affiliate of Colossal is hiring a Scientist to develop and implement genome engineering strategies for non-model mammalian organisms. The candidate will design and produce reagents for CRISPR/Cas9, prime editing, base editing, and additional modalities as needed; develop strategies for multiplex genome editing coupled with comprehensive genotyping assays; and independently analyze editing outcomes using appropriate bioinformatics tools. This hands-on role requires a scientist with established technical expertise who can contribute immediately, innovate, and collaborate closely with Cell Engineering teams responsible for cellular delivery and production of edited cell lines.
This position is based on-site in Dallas, TX. Relocation assistance is available.
Duties and Responsibilities:
- Design, execute, and optimize CRISPR/Cas9, prime editing, and base editing strategies, including multiplex editing of multiple genomic targets.
- Design and generate guide RNAs, pegRNAs, donor templates, expression constructs, and other genome editing reagents; oversee their validation and quality control.
- Innovate and troubleshoot editing strategies to improve efficiency, specificity, reproducibility, and scalability in non-model mammalian systems.
- Apply knowledge of molecular genetics and DNA repair pathways to guide editing strategy, reagent design, troubleshooting, and interpretation of complex editing outcomes.
- Independently design comprehensive genotyping assays to confirm intended edits, quantify editing efficiencies, and identify unintended or complex editing outcomes.
- Analyze Sanger and next-generation sequencing data using appropriate bioinformatics tools and pipelines; interpret allelic outcomes and use results to guide experimental decisions.
- Work closely with Cell Engineering scientists to coordinate reagent transfer, experimental designs, editing readouts, and optimization of workflows.
- Plan and execute experiments to meet project milestones; communicate results through reports, presentations, and team meetings.
- Maintain accurate experimental records, reagent documentation, and organized laboratory workflows.
Required Skills and Abilities:
- Demonstrated hands-on expertise in mammalian CRISPR/Cas9 genome editing and at least one advanced editing modality (prime editing or base editing), with working knowledge of the other.
- Demonstrated experience designing and executing multiplex genome editing strategies and troubleshooting complex editing outcomes.
- Strong foundational knowledge of molecular genetics, genome organization, and DNA repair mechanisms, including mismatch repair (MMR), homology-directed repair (HDR), and non-homologous end joining (NHEJ), and their implications for editing efficiency, precision, and outcomes.
- Advanced molecular biology skills, including guide design, DNA assembly and cloning, nucleic acid reagent preparation, and sequence verification.
- Proven ability to independently design robust genotyping assays, including junction and allele-specific PCR, sequencing-based assays, and quantitative evaluation of editing outcomes.
- Hands-on proficiency with bioinformatics tools for analysis of long- and short-read NGS editing data, including interpretation of indels, substitutions, and mixed or multiplex genotypes.
- Demonstrated scientific innovation, independent experimental design, critical data analysis, and creative problem-solving.
- Ability to execute established workflows independently from the outset and adapt quickly in a fast-paced, collaborative startup environment.
- Strong organizational skills, attention to detail, and written and oral communication skills.
Preferred Experience:
- Hands-on experience with both prime editing and base editing, including editor and guide optimization.
- Experience with complex genomic modifications, HDR donor design, large insertions, or integrase/recombinase-based approaches.
- Experience with in vitro transcription, RNA purification, and reagent QC.
- Experience evaluating off-target editing, structural variants, copy number, and allele phasing using sequencing or orthogonal molecular assays.
- Experience with genome editing analysis pipelines and reproducible computational workflows.
Required Education and Experience:
- PhD in genetics, molecular biology, genome engineering, synthetic biology, or a related field.
- Demonstrated independent, hands-on experience developing and applying genome editing strategies in mammalian systems; candidates must be ready to contribute immediately with minimal technical training.
What Colossal Offers Full-Time Employees:
- Medical, dental, and vision coverage
- Excellent paid time off and company holidays so you can rest and recharge
- Flexible spending accounts (FSA)
- Company matched 401k retirement plan
- Paid parental leave at 100% salary for up to 12 weeks
- Education reimbursement
- An opportunity to help us return the Earth to a healthier state
The team at Colossal is committed, colorful, passionate, intelligent, collaborative, creative, experienced, scientific and world-class. That sounds like a lot to fit into one building. That’s why we are spread out in several locations that include laboratories, test facilities, academic institutions, libraries and offices.
Through it all, however, we maintain a culture of positivity, hope, happiness and belief that we’re doing something big. Something Colossal.
Colossal is proud to be an equal employment opportunity workplace. We welcome people from all backgrounds as well as celebrate and support diversity. We are committed to providing an inclusive environment of mutual respect that is free from discrimination and harassment so everyone can thrive.
EEO is the Law
Search Firm Representatives: Colossal does not accept unsolicited assistance from search firms. No fees will be paid for a hired candidate where no pre-existing agreement is in place. We handle most recruitment in-house.
Colossal is proud to be named a Best Place to Work by BuiltIn for 4 years in a row across multiple categories in 2023, 2024, 2025, and 2026:
- #1 on the 50 Best Startups to Work For in Dallas in 2023!
- 100 Best Midsize Places to Work in Dallas in 2024 & 2025
- 100 Best Places to Work in Dallas, TX (All Size Employers) in 2024, 2025, and 2026.
Built In 2026 Award Lists
Great Place to Work Certification Page
Most Loved Workplace Certification Page - Proud to be certified as a most loved workplace including: most loved CEO, most loved workplaces for LGBTQ+, most loved workplaces for women, and most loved workplaces for young professionals.
Newsweek's Most Loved Workplaces 2024 Award List - Excited to be amongst the winners of Newsweek's 2024 Most Loved Workplaces!



