Bardet–Biedl syndrome is linked to DNA markers on chromosome 11 q and is genetically heterogeneous

Abstract

Bardet-Biedl syndrome (BBS) is an uncommon autosomal recessive condition characterized by mental retardation, post-axial polydactylia, obesity and pigmentary retinopathy. We performed linkage analysis in 31 multiplex BBS families and report significant linkage with two markers on chromosome 11q, PYGM and AFM164zf12 (D11S913). Homogeneity testing demonstrates genetic heterogeneity within our set of families. Our data imply that a major gene, BBS1, is located on chromosome 11q, although mutations at other loci may also be associated with this phenotype.

A 3-Mb Contig from D11S987 to MLK3, a Gene-Rich Region in 11q13: Figure 1.

“…MLK3 cosegregates with PYGM; FRA1, D11S913, HNP36, D11S460, PC, ACTN, D11S703, D11S951E, D11S1956E, and WI-12191 with SEA;and D11S987 and D11S807 (Alu-PCR) with GSTP1. Genetic markers (PYGM, D11S913, D11S460, D11S987, and D11S807) used previously in family studies (Nakamura et al 1989;Larsson et al 1992;Thakker et al 1993;Leppert et al 1994;Weber et al 1994;Smith et al 1995b), as well as genes/expressed sequence tags (ESTs) (MLK3, FRA1, PC, ACTN, D11S951E, D11S1956E, WI-12191, HNP36, SEA, and GSTP1) were included to integrate the transcription, genetic, and RRH maps.…”

“…In addition to several housekeeping genes, including ␣-actinin 3 (ACTN; Beggs et al 1992) and glutathione Stransferase 1 (GSTP1; Morrow et al 1989), several growth factors, signal transduction molecules, and proteins potentially involved in the cell cycle, including mixed lineage protein kinase 3 (MLK3; Ing et al 1994) and a hydrophobic 36-kD protein delayed early response gene (HNP36; Williams and Lanahan 1995;Williams et al 1997), also map to 11q13. Best's macular dystrophy (Forsman et al 1992), Bardet-Biedl syndrome 1 (BBS1; Leppert et al 1994), insulin-dependent diabetes mellitus 4 (IDDM4; Davies et al 1994), and spinocerebellar ataxia 5 (SCA5; Ranum et al 1994) are among the disease loci whose genes reside in this region that yet remain to be identified.…”

Prenatal diagnosis of Bardet–Biedl syndrome by targeted second‐trimester sonography

“…The disorder is genetically heterogeneous with five genetic loci mapped to date: BBS1 (MIM 209901) that maps to 11q 3 and apparently is the most common 4,5 ; BBS2 (MIM 209900) that maps to 16q21 6 ; BBS3 (MIM 600151) that maps to 3p13-p12 7 ; BBS4 (MIM 600374) that maps to 15q22.3-q23 8 and BBS5 (MIM 603650) that maps to 2q31 9 .…”

End Stage Renal Disease, Differential Diagnosis, A Rare Genetic Disorder: Bardet–Biedl Syndrome: Case Report and Review

“…BBS is an uncommon autosomal recessive condition characterised by mental retardation, post axial polydactyly, obesity and pigmentary retinopathy [3]. Detailed biochemical mechanisms that lead to BBS is still unclear.…”