Brain atlas maps 25.5 million basal ganglia cells linked to Parkinson's and schizophrenia

A new map of the basal ganglia

Scientists in the BRAIN Initiative cell atlas network have published the most detailed multi-species cell atlas of the basal ganglia to date. The basal ganglia are deep brain structures that help control movement, habits, emotions and decisions. The papers appeared on Thursday, 12 November 2026, in journals of the Cell Press family, and the package is described as between 26 and 28 papers depending on the account. Hundreds of scientists from more than 50 institutions in nine countries took part. The wider BRAIN project was launched in 2014 by then US president Barack Obama, and its results are often compared with the Human Genome Project.

What the atlas contains

The researchers profiled about 25.5 million cells: roughly 21 million from human brains, 3 million from macaques and 1.5 million from marmosets. Using single-cell molecular analysis, they mapped which genes are active in each cell population and combined that with data on how DNA activity is regulated and where cells sit in tissue. Comparing species matters because animal models cannot be manipulated in the same way in people, so the atlas offers a common framework for matching human cells with those of other primates. Evan Macosko, a Harvard Medical School associate professor who worked on the research, called the basal ganglia the "grand central" for many brain diseases and said the map is meant to serve as a template for others.

“We really need to have a clear understanding of how these different brain areas function if we're going to try and fix them.”

Humans21

Macaques3

Marmosets1.5

Humans

21 million cells

Macaques

3 million cells

Marmosets

1.5 million cells

Data from the article text

Findings linked to disease

The consortium reported a previously unknown cell type, STR D2 SMYD2-HTR7, where genetic risk signals linked to schizophrenia and bipolar disorder are concentrated. Researchers say this allows future work to focus on people who carry the same genetic disease signal. A second study found that an amended version of an existing Parkinson's gene therapy reduced tremors more effectively in animals and is less invasive. A further strand of work found genetic changes in certain basal ganglia cell types that could play a role in autism.

A 'Google Maps' for the brain's central station

The authors describe the atlas as a kind of 'Google Maps' of the basal ganglia, showing where each cell sits and which of its several hundred genes is in use. Fenna Krienen, a Princeton neuroscience professor and one of the project's leaders, compares the effort to an early version of the Human Genome Project. That earlier work gave researchers a shared reference for genes, and this effort aims to do something similar for brain cells and their molecular features. Margarita Behrens, a researcher at the Salk Institute in La Jolla, California, said in a centre statement that the atlas lets scientists identify and locate each cell in the region precisely.