A Rare Contiguous Gene Deletion Leading to Trichothiodystrophy Type 4 and Glutaric Aciduria Type 3

• Published in: Molecular syndromology 2023-04, Vol.14 (2), p.136-142
• Main Authors: Demir, Engin, Doğulu, Neslihan, Tuna Kırsaçlıoğlu, Ceyda, Topçu, Vehap, Eminoglu, Fatma Tuba, Kuloğlu, Zarife, Kansu, Aydan
• Format: Article
• Language: English
• Subjects: Novel Insights from Clinical Practice
• ISSN: 1661-8769; 1661-8777
• DOI: 10.1159/000526393

Introduction: Trichothiodystrophy type 4 and glutaric aciduria type 3 are rare autosomal recessive disorders caused by biallelic variants in the MPLKIP and SUGCT genes on chromosome 7p14, respectively. Trichothiodystrophy type 4 is characterized by neurologic and cutaneous abnormalities. Glutaric aciduria type 3 is a rare metabolic disorder with inconsistent phenotype and elevated urinary excretion of glutaric acid. Case Presentation: Here, we report on an infant presenting with hypotonia, failure to thrive, microcephaly, dysmorphic features, brittle hair, hypertransaminasemia, and recurrent lower respiratory tract infections. Microarray analysis revealed a homozygous microdeletion involving the MPLKIP and SUGCT genes, which are located close to each other. Conclusion: Copy number variations should be considered in patients with coexisting clinical expression of different genetic alterations. To the best of our knowledge, our patient is the second case with co-occurrence of trichothiodystrophy type 4 and glutaric aciduria type 3, resulting from a contiguous gene deletion.