# Integrating Human Genetics and Single-Cell Functional Assays to Elucidate Mechanisms of Fetal Hemoglobin Regulation

> **NIH NIH R56** · BOSTON CHILDREN'S HOSPITAL · 2020 · $311,520

## Abstract

Project Summary/ Abstract
Studies conducted over the past decade have helped uncover key regulators of fetal hemoglobin (HbF)
expression, including the major HbF repressor, BCL11A. Despite these considerable advances, which have
largely been inspired by studies of common and rare human genetic variation, many questions remain.
Specifically, the precise mechanisms by which HbF is regulated are unclear. Studies of HbF regulation have
been constrained by two challenges. First, nearly all reported genetic mutations/ deletions with large effects upon
HbF expression have generally been assessed in one or a limited number of individuals, restricting the inferences
that can be made from such findings. Second, existing cellular models for studies of HbF regulation have
numerous limitations and do not faithfully recapitulate observations made in vivo or in primary cells. To overcome
these two issues, here we propose to utilize genetic data from a large population-based study we have already
conducted and couple this with a new single cell-derived functional assay using cutting-edge genome editing
tools to determine the impact of naturally-occurring deletions and predicted cis-regulatory elements on HbF
levels. We have studied variation in HbF levels in a population of over 86,000 individuals and focused our genetic
analysis on rare individuals harboring elevated HbF. This has enabled us to identify several mutations and
deletions causing increased HbF expression. However, there is considerable variation noted even in individuals
with the same deletion/ mutation, suggesting that a complex genetic architecture determines HbF levels. We
plan to employ a single cell-derived genome editing functional assay to assess the impact of creating specific
perturbations in an isogenic setting on HbF expression. We will couple this assay with innovative genetic
mapping approaches using our rich population genetic dataset. These studies will enable us to nominate novel
cis-regulatory elements that impact HbF levels, as well as the trans-acting factors that function through these
cis-elements. Success in the proposed studies should enable new insights into HbF regulation and facilitate the
development of curative approaches for sickle cell disease and b-thalassemia.

## Key facts

- **NIH application ID:** 10146662
- **Project number:** 1R56DK125234-01
- **Recipient organization:** BOSTON CHILDREN'S HOSPITAL
- **Principal Investigator:** Vijay Ganesh Sankaran
- **Activity code:** R56 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2020
- **Award amount:** $311,520
- **Award type:** 1
- **Project period:** 2020-08-15 → 2021-07-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10146662

## Citation

> US National Institutes of Health, RePORTER application 10146662, Integrating Human Genetics and Single-Cell Functional Assays to Elucidate Mechanisms of Fetal Hemoglobin Regulation (1R56DK125234-01). Retrieved via AI Analytics 2026-05-25 from https://api.ai-analytics.org/grant/nih/10146662. Licensed CC0.

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