ABCB4 Gene Mutations in Intrahepatic Cholestasis of Pregnancy and Controls

Mutations and Polymorphisms of Gene ABCB4 Among Women Suffering From Intrahepatic Cholestasis of Pregnancy. A Study With a Control Group.

Mutations of the ATP binding cassette subfamily B member 4 (ABCB4) gene, a gene involved in a subtype of progressive familial intrahepatic cholestasis, have been reported in women suffering from intrahepatic cholestasis of pregnancy. The true incidence and the role of these ABCB4 gene mutations in patients suffering from intrahepatic cholestasis of pregnancy have not been clearly established.

The aim of the present study is to describe the nature and frequency of these mutations in a series of patients with intrahepatic cholestasis of pregnancy and to compare with a control group of pregnant women without intrahepatic cholestasis of pregnancy.

Intrahepatic cholestasis of pregnancy was defined by pruritus and elevated serum alanine aminotransferase activity or bile acid concentration, with recovery after delivery. Patients with intercurrent liver disease were excluded.

The entire ABCB4 gene coding sequence and the promoter region were analyzed, during the routine medical management, by single strand conformation polymorphism and/or sequencing in 50 unrelated Caucasian patients with intrahepatic cholestasis of pregnancy.

The genomic variants detected in these patients with intrahepatic cholestasis of pregnancy will be sought in 100 control women from Caucasian origin recruited in the same hospital.

For the control group :

Inclusion Criteria:

• pregnant woman (age > 18 years) during the third trimester
• caucasian and born in France
• multiparous (with at least 2 full term pregnancies)
• with informed written consent

Exclusion Criteria:

• generalized pruritus and/or liver disease during pregnancy
• liver disease secondary to oral contraception
• Chronic liver disease
• disease during current pregnancy