What causes café-au-lait spots?

What causes café-au-lait spots?

An increase in the number of skin cells (melanocytes) that produce the protective pigment that darkens skin (melanin) in the thin outer layer of your skin (epidermis) causes café-au-lait (CAL) spots. The reason for the increase in melanocyte cells is unknown.

people diagnosed with neurofibromatosis type 1 (NF1) have CAL spots due to a mutation of the _NF1 gene. The NF1_ gene prevents cells from growing too quickly, which causes melanocytes to produce too much melanin in your skin.

Sometimes the NF1 gene mutation occurs randomly without being present in a person’s family history while others can inherit this condition from their parents if one of their parents has a mutated copy of the NF1 gene (autosomal dominant). Unlike all other autosomal dominant conditions that only need one mutated gene to activate the condition in the child, NF1 does not trigger until later during a person’s lifetime when a genetic mutation of their second copy of the NF1 gene occurs.