Tunisian and international researchers have, for the first time, identified cases of Primary Bile Acid Synthesis Defects (BASD) in Tunisia. BASD is a rare genetic liver disease impacting bile acid production. The study, conducted at La Rabta University Hospital in Tunis, revealed a novel genetic variant linked to one of the deficiencies. This discovery marks a significant step towards understanding and potentially treating this condition within the Tunisian population. These findings open avenues for further research into the genetic basis of liver diseases in the region. The research highlights the growing capabilities of Tunisian medical science and international collaborations in addressing rare health challenges. This identification allows for more accurate diagnosis and potential for targeted therapies.