Segmental Overgrowth Syndromes

Introduction

We offer a next generation sequencing screen of the whole coding sequence of PIK3CA and PTEN, as well as targeted screening of hotspot exons in PIK3R2, AKT1, AKT3, mTOR and CCND2. These genes are part of the phosphoinositide 3-kinase PI3K-Akt signalling pathway and both germline and post-zygotic mutations in these genes have been described associated with many segmental overgrowth syndromes.

Referral information

We offer mutation scanning in affected individuals and recommend testing a sample of DNA extracted from the overgrowth tissue to maximise the chances of mutation detection. The umbrella term of ‘segmental overgrowth syndromes’ encompasses disorders such as such as Megalencephaly-Capillary Malformation (MCM/MCAP) syndrome, Megalencephaly-Polymicrogyria-Polydactyly-Hydrocephalus (MPPH) syndrome, Congenital Lipomatous Overgrowth Vascular Malformations, Epidermal Nevi and Skeletal abnormalities (CLOVES syndrome), Proteus syndrome and Cowden syndrome.

Price & reporting times

NHS referrals to this service are paid for where there is an existing specialist commissioning contract for genetic testing. In other cases please contact the lab for prices.

Test	Price (NHS)	Price (non-NHS)	TRT
Whole coding sequence of PIK3CA, PTEN; targeted exons of PIK3R2, AKT1, AKT3, mTOR, CCND2	POA	POA	56 calendar days
Single mutation test	POA	POA	14 calendar days

Test validation & quality assurance - information for users

100% of target exons are covered and the test is validated down to a mutation level of 4%.

Sample requirements

4ml EDTA blood sample and/or affected fresh tissue sample. If testing for second lineage a buccal swab will be accepted.

Referral guidelines

Please see our referral guidelines for more information.

OMIM Number(s) - 602501, 603387, 612918, 176920, 158350

Gene(s) - PIK3CA, PIK3R2, AKT1, AKT3, mTOR, CCND2, PTEN