The brain is a complex organ and the mutation in one of its gene can have far-reaching consequences. This is precisely what happened in the case of a young boy in the US whose brain was missing a set of cells called microglia because of the mutation of gene CSF1R. According to the report by The Atlantic it wasn’t anything like what the doctors had seen before.
The rare occurrence was caused by the inheritance of two faulty copies of the same gene, one inherited from each parent who both carried the rare gene since they’re cousins. The presence of the mutation in the parents also left them prone to the disorder.
Researchers are now realising that microglia is responsible for directing and influencing brain development.