CASE REPORT
Case report of twins with Bardet-Biedl syndrome exhibiting a rare mutation in the TTC8 gene
1
Students Scientific Group of Clinical Genetics, Jagiellonian University Collegium Medicum, Kraków, Poland
2
Department of Paediatric Nephrology and Hypertension, Jagiellonian University Collegium Medicum, Kraków, Poland
Submission date: 2024-06-23
Final revision date: 2024-08-12
Acceptance date: 2024-08-19
Publication date: 2024-09-30
Corresponding author
Agnieszka Murawska
Students Scientific Group of Clinical Genetics, Jagiellonian University Collegium Medicum, Kraków, Poland
Students Scientific Group of Clinical Genetics, Jagiellonian University Collegium Medicum, Kraków, Poland
Pediatr Pol 2024;99(4):378-384
KEYWORDS
TOPICS
ABSTRACT
Bardet-Biedl syndrome (BBS) is a rare, autosomal recessive disorder, resulting from mutations in various genes, including TTC8. Abnormal variants in this gene were found in the case of our patients – twin sisters diagnosed with BBS. Next-generation sequencing revealed variants in the TTC8 gene: c.-104G>A [NM_001288783, rs119103286] and c.635T>C [NM_144596], which are associated with BBS type 8. The variant found in the patients’ mother was c.-104G>A, and in the patients’ father was c.635T>C, but they did not exhibit any BBS symptoms. Both twins presented several symptoms characteristic of BBS, such as retinopathy, visceral obesity, postaxial polydactyly, renal dysfunction, cognitive impairment, facial dysmorphia, and dental abnormalities. Table 1 compares BBS to other diseases, to facilitate differential diagnosis. Table 2 shows the symptoms of BBS and their frequency of occurrence and Table 3 compares cases of BBS with TTC8 mutation found in the literature.
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