Borjeson-Forssman-Lehmann Syndrome (BFLS) is an X-linked mental retardation syndrome associated with mutations to PHF6. The vast majority of affected patients are males, but females may rarely be affected.

Gene: PHF6 (PHD finger protein 6)

Location: X-chromosome


Occurrence: de novo, typically with a large deletion


Patient: female



(1) intellectual disability

(2) tapered fingers

(3) variable irregular teeth

(4) large ears

(5) variable abnormalities of toes (syndactyly, wide sandal gap, short and broad)

(6) variable coarse face with deep set-eyes

(7) signs of mosaicism: mild body asymmetry and striated skin pigmentation

(8) variable CNS anomalies

(9) variable seizures


The patient may have a skewed X chromosome inactivation pattern on the AR gene CAG-repeat X-inactivation test.


The diagnosis requires gene sequencing to find the specific gene mutation.

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