Postdoctoral Fellow

Pfizer, Cambridge, MA | Feb 2022 – Feb 2025 (3 years)
Bar chart illustrating the inherited threshold model of disease. The first bar shows complete penetrance in variant carriers; subsequent bars show decreasing penetrance due to common genetic modifiers.
Inherited threshold model of disease. This chart illustrates how common genetic modifiers influence the penetrance of rare monogenic diseases. The left bar shows complete penetrance: all carriers of a rare pathogenic variant (blue) are affected. The other bars represent variable penetrance, as seen in conditions like cardiomyopathies.

Summary

  • Organized genetic and medical data leveraged from self-reports, electronic health records, and ~500K exomes in the UK biobank and generated version-controlled code with git to ensure reproducibility

  • Leveraged latest update of UK biobank to identify a sufficiently sized cohort of known and novel cardiomyopathy variant carriers to improve upon previous studies without adequate statistical power

  • Calculated PRS from relevant GWAS and evaluated logistic, cox, and linear regression to quantify the association of common variants on disease penetrance, onset, and severity among the rare pathogenic variant carriers and use the results to provide genetic insight for decreasing disease outcomes

  • Articulated technical genetic study in internal symposiums to showcase my work to multidisciplinary audiences including nonsubject matter experts (eg. biologists, leadership)

Publications

Common genetic modifiers influence cardiomyopathy susceptibility among the carriers of rare pathogenic variants

Klasfeld, S. J., Knutson, K. A., Miller, M. R., Fauman, E. B., Berghout, J., Moccia, R., & Kim, H. I.

Human Genetics and Genomics Advances • 2025

Presentations

Coding cis pQTLs from proteogenomic data allow evaluation of the performance of missense variant effect predictions and the utility of their application to rare variant association analyses

Klasfeld, S., Fauman, E.B., Miller, M.R., Moccia, R., & Kim, H.I.

Poster American Society of Human Genetics • Denver, CO • November 5, 2024

Common genetic modifiers influence disease risk in carriers of rare pathogenic cardiomyopathy variants

Klasfeld, S., Moccia, R., Knutson, A., Berghout, J., & Kim, H.I.

Poster Pfizer Worldwide Research, Development and Medical Postdoc Symposium • Cambridge, MA • November 1, 2023

Genetic modifiers illuminate clinical phenotype penetrance in carriers of rare cardiomyopathy-causal variants

Klasfeld, S., Moccia, R., Knutson, A., Berghout, J., & Kim, H.I.

PowerPoint slides Pfizer Worldwide Research, Development and Medical Postdoc Symposium • Cambridge, MA • November 2, 2023

Genetic modifiers illuminate frequency and penetrance of clinical and subclinical phenotypes in carriers of rare cardiomyopathy-causal variants

Klasfeld, S., Moccia, R., & Berghout, J.

Poster Pfizer Worldwide Research, Development and Medical Postdoc Symposium • Cambridge, MA • November 2, 2022
References
UK Biobank Polygenic Risk Scores

More Work Experiences

Independent Contractor

Genscience, Remote | Sep 2025 – Present
View

Graduate Student Researcher

University of Pennsylvania, Philadelphia, PA | Aug 2015 – Feb 2022 (6 years)
View