Jacobsen syndrome

Jacobsen Syndrome, also known as 11q deletion disorder, is a rare congenital disorder resulting from deletion of a terminal region of chromosome 11 that includes band 11q24.1. It can cause intellectual disabilities, a distinctive facial appearance, and a variety of physical problems including heart defects and a bleeding disorder. The syndrome was first identified by Danish physician Petra Jacobsen,^[1] and is believed to occur in approximately 1 out of every 100,000 births.

Possible characteristics

• Heart defects
• Mild to severe intellectual disabilities
• Low-platelets (thrombocytopenia)
• Facial/skeletal (dysplasia)
• Wide-set eyes caused by trigonocephaly
• Folding of the skin near the eye (epicanthus)
• Short, upturned nose (anteverted nostrils)
• Thin lips that curve inward
• Displaced receding chin (retrognathia)
• Low-set, misshapen ears
• Permanent upward curvature of the pinkie and ring fingers (camptodactyly)
• Large great toes/Hammer toes

In addition, patients tend to be shorter than average and have poor psychomotor skills.

The majority of Jacobsen syndrome cases are not familial in nature, resulting from a spontaneous mutation occurring in a single parental gamete. However, some instances of familial disease resulting from local chromosome fragility or an unbalanced translocation have been described.

References

Sources

• European Chromosome 11 Network - Support group for patients with chromosome 11 disorders, their families and relatives

• Orthoseek - Specializes in pediatric orthopedics and pediatric sports medicine