Neurofibroma is -
Ans. is 'a' i.e., Autosomal dominanto Neurofibromatosis comprises of two distinct disorders -Neurofibromatosis INeurofibromatosis IIo The genes for these are located on different chromosomes,o Both are inherited in an autosomal dominant pattern.NF-1: Neurofibroma gene on chromosome 17.NF-2: Neurofibroma gene on chromosome 22.Neurofibromatosis ripe I fVon-Recklinghew sen disease)o NF-1 is diagnosed when any two of the following seven signs are present.Six or more cafe-au-lait maculeso > 5 mm inprepupertat individualso > 15 mm in postpubertal individualso Cafe-au-lait spots are the hallmark of neurofibromatosis and are present in almost 100% of the patientAxillary or inguinal frecklingTwo or more Lisch nodules.o Lisch nodules are hamartomas located within the iris.Two or more neurofibroma or one plexiform neurofibroma.o Typically involve the skin, but may be situated along peripheral nerves and blood vessels,o They are small, rubbery lesions with a slight purplish discoloration of the overlying skin.A distinctive osseous lesion.o Sphenoid dysplasia or cortical thinning of long bones.Optic gliomaA first degree relative with NF-1o Other findings are : -o Pseudoarthrosis of the tibia.o Scoliosis is the most common orthopedic problem in NF-1 but is not specific enough to be included as diagnostic criteria.o Short Statureo Mental retardation, epilepsyo Hypertensiono Aqueduct! stenosis with hydrocephaluso Meningiomas, ependymomas, Astrocytomas, pheochromocytomas.o NF-1 is caused by mutation In NF-1 gene on chromosome 17 which encodes protein neurofibromin-1.Neurofibromatosis type -2o NF-2 may be diagnosed when one of the following two features are present.Bilateral acoustic neuroma - Most distinctive featureA parent, sibling or child with NF-2 and either unilateral eighth nerve masses or any two of the following - Neurofibroma, meningioma, glioma, Schwannoma or juvenile post-subcapsular cataract.o NF-2 is caused by a mutation in NF-2 gene on chromosome 22 that encodes for protein neurofibromin 2, Schwannomin or merlin.
Autosomal dominant
Autosomal recessive
X-finked recessive
X-linked dominant