In a second family (F2) with a father (I.2) of Moroccan and a mother (I.1) of French descent, a female with CH and thyroid gland ectopia (P4, II.1) had a heterozygous TUBB1 mutation (c.318C>G, p.Y106X; Fig 1). Here, TUBB1 is linked to cyclic hematopoiesis.