Disease Information for Borjeson-Forssman-Lehmann Syn/BFLS (xq26.3): Definition

  • Xq26_2 gene locus; The features of this syndrome are severe mental defect, epilepsy, hypogonadism, hypometabolism, marked obesity, swelling of subcutaneous tissue of face, narrow palpebral fissure, and large but not deformed ears; Three females who might be carriers had moderate mental retardation; with a characteristic facial appearance which included prominent superciliary ridges, deep-set eyes, ptosis, and large ears; no reliable means of identifying heterozygotes; The differential diagnosis includes Prader-Willi, Coffin-Lowry, and Bardet-Biedl syndromes; Generally, in the first year, the babies are floppy, with failure to thrive, big ears, and small external genitalia; As schoolboys, the picture is one of learning problems and moderate short stature, with emerging truncal obesity and gynecomastia; The toes are short and fingers tapered and malleable; In late adolescence and adult life, the classically described heavy facial appearance emerges; Some heterozygous females showed milder clinical features such as tapering fingers and shortened toes; Significant learning problems were found in 20%, and skewed X inactivation in 95%; X-linked recessive; Height Short stature Weight Moderate obesity; Head Microcephaly Face coarse facies; Prominent supraorbital ridges; Ears Large ears; Eyes ;Deep-set eyes; Nystagmus; Ptosis; Poor vision; Narrow palpebral fissures; Breasts; Gynecomastia, postpubertal; external genitalia, male ;Small penis; Internal genitalia, male; Small, atrophic testes; Cryptorchidism; hypoplastic prostate; Skull; Thick calvarium; Spine; Narrow cervical spinal canal; Mild scoliosis; Kyphosis; Scheuermann-like vertebral changes; Hands; Hypoplastic distal and middle phalanges; Soft, fleshy hands; Tapering fingers; Feet; Short toes; Widely spaced and flexed toes; Central nervous system; Severe mental retardation (IQ 10-40); Hypotonia; Abnormal EEG (poor alpha rhythms); Seizures; Delayed puberty; Majority of female carriers have skewed X-inactivation (inactivation of chromosome containing the PHF6) mutation)

    Some female heterozygotes express phenotypic features (eg, coarse facies, mild mental retardation)---------------------------

    Borjeson Syndrome is a rare genetic disorder primarily characterized by an unusual facial appearance, mental retardation, obesity, seizures, delayed sexual development, and/or poor muscle tone (hypotonia); The disorder is transmitted as an X-linked recessive trait and therefore is usually fully expressed in males only; However, females who carry a single copy of the disease gene (heterozygous carriers) may manifest certain, usually more variable features of the disorder-------------[WEBMD 2005]---------