“Larsen Syndrome”, Victor McKusick, Mendelian Inheritance in Man, 1966. 拉森综合症。(LRS).

Here I present: “Larsen Syndrome”, Victor McKusick, Mendelian Inheritance in Man’, 1966. 拉森综合症。(LRS).

INTRODUCTION.

Larsen syndrome (LRS) is an osteochondrodysplasia characterized by large-joint dislocations and characteristic craniofacial abnormalities. The cardinal features of the condition are dislocations of the hip, knee and elbow joints, with equinovarus or equinovalgus foot deformities. Spatula-shaped fingers, most marked in the thumb, are also present. Craniofacial anomalies include hypertelorism, prominence of the forehead, a depressed nasal bridge, and a flattened midface. Cleft palate and short stature are often associated features. Spinal anomalies include scoliosis and cervical kyphosis. Hearing loss is a well-recognized complication.

Filamin B (truncated actin binding protein 278 homolog) is a cytoplasmic protein which in humans is encoded by the FLNB gene.  There is evidence that Larsen syndrome is caused by mutation in FLNB on cytogenetic location 3p14.3 and genomic coordinates 3:58,008,422-58,172,251 .   The screenshot of the FLNB gene 163,830 bp (base pairs) of DNA sequence length is shown BELOW.  Nine (9) other genes besides FLNB on the cytogenetic location are listed BENEATH.