People who will be eligible to be asked about participation in the research project are individuals who seek planned care for surgery on their gallbladder due to gallstone disease. The group of patients is chosen as they can represent a normal material that enables comparison with hernia-specific disease in the abdominal wall.

Basic data such as height, weight, sex, age, medication and ASA class will be collected in the form of a study form and stored in a database in a pseudonymised form. During the sampling of biological material, the test subjects will be under general anesthesia, which is why the sampling will not mean increased pain or discomfort other than what is standard after a gallbladder operation with the minimally invasive technique. No additional wound area will be added to the test subjects as the sample pieces are taken from the area at the umbilicus where one operates by default. The sampling is not planned to be repeated, but is performed at the time when the patients perform their cholecystectomy. During the sampling, centimeter-sized pieces of skin, fatty tissue, connective tissue and muscle are taken. Furthermore, serum and plasma will be collected. Two tubes of blood samples (10 ml total) are taken, centrifuged and pipetted before being frozen for later analysis. Pieces of tissue are placed in formalin before transport to the laboratory. The study form regarding the patient's basic state of health will be filled in by the operator on the day of surgery and will be stored pseudonymized when the research subject is assigned a study number.

Patients who are troubled by gallstone disease and are referred for minimally invasive surgery of the gallbladder at the surgical center Västerbotten in Skellefteå will receive oral and written information and will be asked to participate in the study. Approximately 200 cholecystectomies are performed annually at Skellefteå hospital. We understand that within a reasonable period of time it will be possible to include 40 patients, which is the goal, also taking into account the exclusion criteria that exist. The inclusion of patients is expected to take approximately one year

Inclusion Criteria:

- Individuals seeking planned care for surgery on their gallbladder due to gallstone disease

Exclusion Criteria:

• Disseminated cancer,
• Ongoing acute inflammation of the gallbladder,
• Known connective tissue disease,
• Cortisone medication,
• BMI >35,
• Clinically measured rectus diastasis of >4 cm and/or concurrent abdominal wall hernia
• Patients operated for abdominal wall hernia

People who will be eligible to be asked about participation in the research project are individuals who seek planned care for surgery on their gallbladder due to gallstone disease. The group of patients is chosen as they can represent a normal material that enables comparison with hernia-specific disease in the abdominal wall