PMC8264126_01
(A) Pathogenic variant and a variant of uncertain significance (VUS) for the STXBP2 gene from ClinVar. The pathogenic variant c.1247-1G>C found in the patient is in a splicing site and therefore is not illustrated in this figure (variation ID: 330555; dbSNP: rs140148806). The VUS found in the patient is indicated by a black arrow (c.704>A; p. Arg235gln). There are 10 pathogenic variants and 81 VUS described for STXBP2 in ClinVar, as shown in the figure. The color legend is indicated in the corner of the figure. (B) Protein alignment for the residue Arg235 (VUS) among five organisms: Homo sapiens, Rattus norvegicus, Mus musculus, Canis lupus familiaris, and Bos taurus. Conservation of the arginine (R) is highlighted in blue. Alignment position among the five species: 257; sequence position: 235.
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F1
This revealed that the patient had biallelic mutations in the STXBP2 gene: one pathogenic variant, c.1247-1G>C (splicing acceptor site), and one VUS, c.704G>A (p.Arg235Gln) (Figure 1).
Peripheral blood counts over time. Hb, hemoglobin; ANC, absolute neutrophil count; ALC, absolute lymphocyte count; Plt, platelet count.
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PMC8264126_01_fped-09-633996-g0002.jpg
F2
Since treatment with this protocol, the patient has been in remission (Figure 2).