# Core B

> **NIH NIH P30** · UNIVERSITY OF CALIFORNIA, SAN DIEGO · 2024 · $375,798

## Abstract

Project Summary/Abstract (Core B: HS Breeding Core)
 The heterogeneous stock (HS) Breeding Core (PI: Dr. Leah Solberg Woods) will maintain an HS rat
colony at the Wake Forest University School of Medicine (WFUSM), and a satellite colony at the University of
California San Diego (UCSD). These colonies will produce and distribute HS rats at a subsidized price to
encourage their widespread use. HS rats were created in 1984 by interbreeding eight inbred rat strains. Since
their creation, HS rats have been maintained as an outbred population for almost 100 generations.
Recombinations have accumulated over those generations, which break the founder chromosomes into small
haplotypes, which is essential for fine-mapping of genetic loci. Dr. Solberg Woods has maintained the HS rat
colony since 2006; the colonies at WFUSM and UCSD are the only HS rat colonies in the world. Over the
last decade, the HS rat Breeding Core supported by our P50 center became a heavily used national
resource. That core sent out more than 16,000 rats to more than 25 universities in the US and to Italy,
Germany and Spain. This core will support numerous funded and submitted grants.
 In addition to providing HS rats, this core also supports a new and innovative paradigm called
RATTACA (RAT Trait Ascertainment using Common Alleles) that uses data collected over the last decade to
predict the phenotypes of newborn HS rats based on their genotype. As we describe, RATTACA can be used
to predict any of the phenotypes that have been the subject of prior genome wide association studies (GWAS)
in HS rats. This allows this core to provide rats that are likely to display extreme phenotypes, somewhat
analogous to what has previously been available using genetically selected lines. RATTACA will allow us to
expand the center’s impact by supporting scientists who are not geneticists. RATTACA prediction works best
when a few rats can be genetically selected from a larger population, making it a perfect complement to an HS
Breeding Core that produces large numbers of HS rats.
 RATTACA rats can be used for unique study designs. For example, we can identify rats that would
show strong susceptibility or resilience to cocaine addiction-like behaviors. Normally, such rats would be
identified based on their observed phenotype. However, differences between such groups might then be due to
the different levels of cocaine exposure in the high and low groups, or to the genetic predisposition that led
them to self-administer different amounts of cocaine. Using RATTACA, cocaine naive groups that are
genetically susceptible or resilient to cocaine addiction-like behavior can be compared; observed differences
must be due to this genetic predisposition. Thus, RATTACA is an innovative experimental paradigm that will be
offered as subsidized service by this core, thus broadening the impact of our center.

## Key facts

- **NIH application ID:** 10935612
- **Project number:** 1P30DA060810-01
- **Recipient organization:** UNIVERSITY OF CALIFORNIA, SAN DIEGO
- **Principal Investigator:** Leah Catherine Solberg Woods
- **Activity code:** P30 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $375,798
- **Award type:** 1
- **Project period:** 2024-09-01 → 2029-05-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10935612

## Citation

> US National Institutes of Health, RePORTER application 10935612, Core B (1P30DA060810-01). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/10935612. Licensed CC0.

---

*[NIH grants dataset](/datasets/nih-grants) · CC0 1.0*