A family with autosomal dominant polycystic kidney disease not linked to chromosome 16p13.3

Two families with blepharophimosis/ptosis/epicanthus inversus syndrome have mutations in the putative forkhead transcription factor FOXL2

Blepharophimosis/ptosis/epicanthus inversus syndrome (BPES) is an autosomal dominant disorder that is characterized by distinctive eyelid abnormalities. Two clinical subtypes have been described in which type I, but not type II, is associated with premature ovarian failure. Both types of BPES are linked to 3q22-23, and the gene has recently been identified as the putative forkhead transcription factor FOXL2. We report mutation screening of FOXL2 in two families with this condition. The two mutations detected were frameshift mutations resulting from a small insertion or duplication within the gene. Both mutations would result in the production of novel carboxyl terminii, one terminating the predicted protein earlier than the wild type, and the other giving rise to a larger protein product, assuming these proteins or their mRNA were not degraded. Based on the present data, this would suggest that the first family should be type I and the second, type II. Although there is evidence of infertility in the first family, all 3 females in the youngest generation have normal pelvic ultrasound and hormone levels, suggesting that the divide between types I and II may not be as distinct as has been suggested.

Linkage analysis in blepharophimosis-ptosis syndrome confirms localisation to 3q21-24

Blepharophimosis-ptosis is an autosomal dominant disorder in which previous chromosome rearrangements have suggested a putative gene location on the long arm of chromosome 3. This paper confirms the location at 3q21-24 with linkage studies in two large families. A lod score of 3·2 was found with D3S1237.

Genetic analysis of 20 families with autosomal dominant adult polycystic kidney disease from South West Thames Region

Twenty families with autosomal dominant polycystic kidney disease from S. W. Thames Region were analysed using markers for chromosome 16p13.3, the site of the common mutation (PKD1). Six families gave a negative lod-score for 3'HVR, the most informative distal marker. This could be explained in four cases by recombination events. Of the two families where this was not an explanation, one, of Italian origin, was unequivocally unlinked for all markers, and the other was more likely to be non-PKD1 than linked to 16p13.3. The Italian family was ascertained through the Blood Pressure Unit, and the other via the Genetic Clinic. No members of either family had ever attended a renal clinic. The remaining 18 families either came via renal clinics, or had at least one member attending such a centre.

A family with autosomal dominant polycystic kidney disease linked to 4q21-23

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