CTNNA1 Familial Expansion Study

Inclusion Criteria:

* 18 years of age and older
* Participants must be carrier, or a first degree relative of a carrier, of a CTNNA1 loss-of-function variant defined as: a variant predicted to lead to protein truncation (nonsense and frameshift variants), a large deletion of one or more exons, or a consensus splice site variant predicted to disrupt splicing in CTNNA1. CTNNA1 loss-of-function variants do not need to be classified as pathogenic or likely pathogenic to be included.
* Participants must be able to understand and read English
* Participants must be able to provide informed verbal or written consent

Exclusion Criteria:

* Less than 18 years of age
* Individuals who do not carry a CTNNA1 loss-of-function variant and are not a first degree relative of a CTNNA1 loss-of-function variant carrier.
* Individuals who cannot speak and read English
* Major psychiatric illness or cognitive impairment that in the judgement of the study investigators or study staff would preclude study participation
* Unable to comply with the study procedures as determined by the study investigators or study staff