Email

heaney@bcm.edu

Positions

Associate Professor

Molecular and Human Genetics
Baylor College of Medicine

Member

Genetics & Genomics Graduate Program
Baylor College of Medicine

Member

Development, Disease Models & Therapeutics Graduate Program
Baylor College of Medicine

Director

Center for Precision Medicine Models
Baylor College of Medicine

Academic Director

Genetically Engineered Rodent Models (GERM) Core
Baylor College of Medicine

Co-Leader, Advanced in Vivo Cancer Models Shared Resource

Dan L Duncan Comprehensive Cancer Center
Baylor College of Medicine

Member

Dan L Duncan Comprehensive Cancer Center
Baylor College of Medicine

Chair

International Mouse Phenotyping Consortium

Addresses

Department of Molecular and Human Genetics (Office)

Baylor College of Medicine
Houston, TX 77030
United States

Education

BS from University Of New Hampshire

01/1998 - Durham, NH United States

PhD from Pennsylvania State University

01/2004 - Hershey, PA United States

Post-Doctoral Fellowship at Case Western Reserve University

01/2010 - Cleveland, OH United States

Professional Interests

• Germ cell developement, infertility, and cancer
• Mammalian genetics
• Mouse models of human diseases
• Genome editing technologies

Professional Statement

In my laboratory we use mouse genetics, genomics and genome editing technologies to catalog gene function and contribution to human disease. Ongoing research includes:

Characterizing genes and developmental pathways that contribute to testicular germ cell tumors (TGCTs). Germ cells arise during embryogenesis as pluripotent-like primordial germ cells (PGCs) that differentiate into mature gametes and ultimately the cells and tissues of an adult organism. Defects during male germ cell development can lead to the formation of TGCTs. In 129 mice, TGCTs arise during embryogenesis as foci of pluripotent embryonal carcinoma cells (EC cells), which differentiate to form teratomas. During embryogenesis, male germ cells normally enter mitotic arrest until after birth and female germ cells initiate the meiotic program, both of which are accompanied by down-regulation of pluripotency. We have identified a defect in this developmental switch as the cause of TGCT initiation. In TGCT susceptible gonads, XY germ cells do not enter mitotic arrest, delay expression of male germ cell differentiation genes, and continue to express core pluripotency factors. Ongoing studies are using genome editing in mice, developmental biology approaches, and single-cell RNA sequencing to (1) characterize mechanisms by which male germ cell sex specification is delayed, (2) test the contribution of a shift in pluripotent states to germ cell transformation into EC cells, (3) functionalize TGCT susceptibility loci identify in human genome-wide association studies, and (4) explore environmental contributions to TGCT risk.

Determining the mechanisms by which gene loss-of-function contributes to infertility. The Knockout Mouse Phenotyping Program (KOMP2), as a part of the International Mouse Phenotyping Consortium (IMPC) has established an infrastructure for high-throughput generation of null alleles and broad-based, adult and embryo phenotyping of knockout mouse lines. To date, 6.5% of the mouse lines characterized by the IMPC demonstrate male and/or female infertility with many novel infertility genes being identified. Ongoing studies are focused on these novel infertility genes with the goals of (1) understanding the cellular and molecular mechanisms by which loss-of-function mutations in these genes contribute to infertility and (2) determining whether these genes are potential targets for novel birth control options.

Characterizing gene and variant contribution to Mendelian diseases. Up to 70% of patients with suspected genetic disease remain undiagnosed likely because their disease-causing variant(s) has yet to be discovered or the clinical significance of identified variants remains unclear. Precision model organisms are important tools aiding in the interpretation of these variants and are critical for testing therapeutic paradigms. The BCM Center for Precision Medicine Models supports local, national, and international programs and individual researchers in the development of precision fly and mouse that will end the diagnostic odyssey of patients with undiagnosed, rare, and Mendelian diseases and serve as resources for pre-clinical studies investigating personalized medicine approaches to their care. The Center uses a variety of genome editing approaches to build mouse models of human disease with the goals of (1) validating new gene-disease relationships, (2) confirming phenotype expansion for known disease genes, and (3) testing new treatment approaches. The Baylor/Rice Genome Editing Testing Center assists researchers with pre-clinical testing of novel genome editing delivery systems and approaches in mouse models. The Center is using novel genome editing reporter mouse models made at Baylor to test the efficacy of new delivery systems and mouse models of human disease to test novel genome editing approaches that may ameliorate or cure disease.

Websites

Selected Publications

• Walkey CJ, et al. "A comprehensive atlas of AAV tropism in the mouse.." Mol Ther. 2025 Mar 5;33(3):1282-1299. Pubmed PMID: 39863928
• Elrick H, et al. "Impact of essential genes on the success of genome editing experiments generating 3313 new genetically engineered mouse lines." Sci Rep.. 2024 Sep 30;14(1):22626. Pubmed PMID: 39349521
• Lanza DG, Mao J, Lorenzo I, Liao L, Seavitt JR, Ljungberg MC, Simpson EM, DeMayo FJ, Heaney JD. "An oocyte-specific Cas9-expressing mouse for germline CRISPR/Cas9-mediated genome editing." Genesis. 2024 Apr;62(2):e23589. Pubmed PMID: 38523431
• Pan X, et al. "De novo variants in FRYL are associated with developmental delay, intellectual disability, and dysmorphic features.." Am J Hum Genet. 2024 Mar 6;S0002-9297(24)00039-9. Pubmed PMID: 38479391

Memberships

International Mammalian Genome Society

Member

Genetics Society of America

Member

International Society for Transgenic Technology

Member

Society for the Study of Reproduction

Member

Funding

BCM Knockout Mouse Production and Phenotyping Project - #UM1 HG006348

NIH/NHGRI

BCM Center for Precision Medicine Models - #U54 OD030165

NIH/OD

BCM/Rice Genome Editing Testing Center - #U42 OD035581

NIH/OD