Laboratory tests revealed leukopenia, neutropenia, lymphopenia and monocytosis (WBC 3,3×10μ3/ μL, 1,6×10μ3/ μL, 1,3 ×10μ3/ μL and 10,9% respectively, ESR and C-reactive protein (CRP) were within limits ESR -12/lh, CRP -0.1 mg/l. The gene discussed is ESR1; the disease is Decreased total neutrophil count.