19 May 2026
: Case report 
Neonatal-Onset Refractory Thrombocytopenia and Anemia Associated With a Homozygous In-Frame NFE2 Duplication
Challenging differential diagnosis, Rare disease, Congenital defects / diseases, Rare coexistence of disease or pathology
Mohammed Shahab Uddin
ABCDEF 1,2,3*, Maan Albehair BFG 4,2,3, Fayez Nashi Motlaq Alshammari BFG 4,2,3, Amr Esmail BFG 4,2,3, Khaled Shafeen BFG 5, Abdullah Bin Hassan BEG 4,2,3, Hana Bawazier ACE 4,2,3
DOI: 10.12659/AJCR.952024
Am J Case Rep 2026; 27:e952024
Figure 3 p45/NF-E2 domain architecture and location of the p.Glu297_Arg300dup in-frame duplication. (A) Full-length schematic of p45/NF-E2 (373 amino acids) showing the transactivation (TA) domain, CNC region, basic DNA-binding region, and leucine zipper. The homozygous in-frame duplication p.Glu297_Arg300dup is indicated within the CNC region, immediately proximal to the basic region. The dashed box highlights the C-terminal bZIP-containing segment shown in panel B. (B) Enlarged view of the C-terminal region (aa 270–373) demonstrating the position of p.Glu297_Arg300dup relative to the CNC, basic, and leucine zipper domains. The lower schematic illustrates the in-frame duplication of residues E297–R300, resulting in repetition of the four–amino acid motif without alteration of the downstream reading frame. Protein coordinates refer to NFE2 isoform 1/RefSeq NP_001129495.1 (373 aa; MANE Select). NLS – nuclear localization signal.