<?xml version="1.0" encoding="US-ASCII"?>
<!-- EDGAR Online I-Metrix Xcelerate Taxonomy Schema, based on XBRL 2.1  http://www.edgar-online.com/ -->
<!-- Version: 6.17.6 -->
<!-- Round: 1 -->
<!-- Creation date: 2012-09-11T16:41:21Z -->
<!-- Copyright (c) 2005-2011 EDGAR Online, Inc. All Rights Reserved. -->
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      <link:roleType roleURI="http://www.mfs.com/role/DocumentDocumentandEntityInformation" id="DocumentDocumentandEntityInformation">
        <link:definition>0011 - Document - Document And Entity Information {Elements}</link:definition>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://www.mfs.com/role/RiskReturn_S000038262Member" id="RiskReturn_S000038262Member">
        <link:definition>0112 - Document - Risk/Return Summary {Unlabeled} (High Yield Pooled Portfolio)</link:definition>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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      <link:roleType roleURI="http://www.mfs.com/role/ShareholderFeesData_S000038262Member" id="ShareholderFeesData_S000038262Member">
        <link:definition>0113 - Schedule - Shareholder Fees</link:definition>
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        <link:usedOn>link:presentationLink</link:usedOn>
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        <link:definition>0114 - Schedule - Annual Fund Operating Expenses</link:definition>
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        <link:usedOn>link:presentationLink</link:usedOn>
        <link:usedOn>link:definitionLink</link:usedOn>
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