case_images: PMC10890899_01
case_images: Whole-exome sequencing results of the patient, her parents, and brother. The patient (a) had a heterozygous frameshift mutation in the PRRT2 gene located in Chr16: 29813703 (NM_145239.2: exon2: c.649dupC (p.Arg217Profs*8)); her healthy mother (c) and brother (d) had the same mutation in the PRRT2 gene; her father (b) had the wild-type PRRT2 gene.
case_images: CRIPE2024-5539799.001.jpg
case_images: PMC10890899_01_CRIPE2024-5539799.001.jpg
case_images: fig1
case_images: A mutation in the PRRT2 gene in the proband was identified (Figure 1(a)), and it was found to have been inherited from the healthy mother (Figure 1(c)). This mutation was also present in her brother (Figure 1(d)), who had also experienced afebrile seizures before the age of two. This mutation was not detected in her father (Figure 1(b)).
case_images: Pedigree of the proband. Patients with the c.649dupC PRRT2 heterozygous mutation are indicated as +/m, while those tested negative for the mutation are indicated by +/+. BFIS refers to benign familial infantile seizures. III2 is the proband with the PRRT2 gene mutation and a phenotype of BFIS and autism spectrum disorder. III4 experienced early onset afebrile seizures on the 3rd day of life, received antiepileptic medication before the age of one, went into remission before age 2, and did not undergo whole-exome sequencing testing. I1, II3, and III3 had BFIS before the age of 2, went into remission without medication, and also did not undergo whole-exome sequencing testing.
case_images: CRIPE2024-5539799.002.jpg
case_images: PMC10890899_01_CRIPE2024-5539799.002.jpg
case_images: fig2
case_images: Considering the classic presentation of seizures, the detection of the same mutation detected in the mother and brother, and the positive family history of other members (Figure 2), a definitive diagnosis of BFIS was made.