Case Report: Hypomyelinating Leukodystrophy Type 20 (HLD20) With Novel CNP Gene Variant.
PMID 40396300 | DOI 10.1002/ajmg.a.64094 · American journal of medical genetics. Part A · 2025
This case report describes a child with hypomyelinating leukodystrophy type 20 (HLD20), a rare neurodegenerative disorder characterized by impaired myelin formation. The patient presented with multiple neurodevelopmental abnormalities, including delayed motor milestones, seizures, and abnormal facial features. Genetic analysis identified a novel homozygous variant, c.295G > T p.(Glu99*), in the CNP gene, which is associated with HLD20. Furthermore, RT-qPCR revealed a significant decrease in the CNP mRNA expression in the patient sample as compared to the control. This case expands the known genetic and clinical spectrum of HLD20 and highlights the importance of comprehensive genetic evaluation for patients with suspected neurodegenerative disorders.
Validated evidence
| Type | Entity | Source evidence | Confidence | Extractor |
|---|---|---|---|---|
| gene | CNP | “Case Report: Hypomyelinating Leukodystrophy Type 20 (HLD20) With Novel CNP Gene Variant.” | 0.98 | hgnc_dict_v1 |
| phenotype | epilepsy | “The patient presented with multiple neurodevelopmental abnormalities, including delayed motor milestones, seizures, and abnormal facial features.” | 0.93 | phenotype_alias_lexicon_v2 |
| variant | p.Glu99* | “Genetic analysis identified a novel homozygous variant, c.295G > T p.(Glu99*), in the CNP gene, which is associated with HLD20.” | 0.95 | hgvs_regex_v1 |