The large size of the TTN gene encoding titin and the existence of numerous isoforms make it difficult to interpret genomic variants. An international consortium provides an update on this issue:
- 12 cases of suspected titinopathy, one of which had already been published, have been the subject of further studies with the aim of determining the pathological nature of certain allelic truncating variants of the TTN gene and attempting to correlate them with the clinic,
- transcript sequencing coupled with studies of pre- and post-natal muscle tissue has enabled a better assessment of the prognosis of the patients concerned,
- on the other hand, a false positive was detected.
Although difficult to carry out routinely, these functional studies are proving very useful for complex cases of autosomal recessive early titinopathy.
