TY - JOUR
T1 - Preimplantation diagnosis of a lysosomal storage disorder by in situ enzymatic activity
T2 - 'Proof of principle' in acid sphingomyelinase-deficient mice
AU - Butler, A.
AU - Henderson, S. C.
AU - Gordon, R. E.
AU - Dagan, A.
AU - Gatt, S.
AU - Schuchman, Edward H.
N1 - Funding Information:
This work was supported by NIH grant R01 HD28607 and a grant from the Fogarty International Center (R03 TW001372).
PY - 2005/1
Y1 - 2005/1
N2 - Genetic diagnosis of preimplantation embryos (PGD) can substantially reduce the chance that at-risk couples have children afflicted with inherited diseases. However, PGD requires DNA,which is usually obtained from single cells following embryo biopsy. In addition, PGD requires that the genetic defect(s) causing the disorder be known. We have therefore developed an alternative to PGD, which we term preimplantation enzymatic diagnosis (PED). PED has several advantages over PGD, including the facts that it does not require embryo biopsy and that the gene defect(s) causing the disorder need not be known. We have demonstrated 'proof of principle' for this approach using embryos obtained from a mouse model (ASMKO mice) of acid sphingomyelinase (ASM)-deficient Niemann-Pick disease, an inherited lysosomal storage disorder. For this technique, fluorescently (BODIPY)-conjugated sphingomyelin was used to detect ASM activity in situ. Wild-type, preimplantation embryos degraded the substrate following a short 'pulse-chase' period, resulting in markedly reduced fluorescence compared to ASMKO embryos, which retained the fluorescent substrate. Thus, the two embryo types could be easily distinguished by fluorescent microscopy. The fluorescent sphingomyelin was not toxic to the embryos, and the entire procedure could be accomplished within 48 h without embryo biopsy. We suggest that PED may be useful for the preimplantation diagnosis of lysosomal storage disorders, and perhaps other enzymatic defects where similar in situ assay methods are available.
AB - Genetic diagnosis of preimplantation embryos (PGD) can substantially reduce the chance that at-risk couples have children afflicted with inherited diseases. However, PGD requires DNA,which is usually obtained from single cells following embryo biopsy. In addition, PGD requires that the genetic defect(s) causing the disorder be known. We have therefore developed an alternative to PGD, which we term preimplantation enzymatic diagnosis (PED). PED has several advantages over PGD, including the facts that it does not require embryo biopsy and that the gene defect(s) causing the disorder need not be known. We have demonstrated 'proof of principle' for this approach using embryos obtained from a mouse model (ASMKO mice) of acid sphingomyelinase (ASM)-deficient Niemann-Pick disease, an inherited lysosomal storage disorder. For this technique, fluorescently (BODIPY)-conjugated sphingomyelin was used to detect ASM activity in situ. Wild-type, preimplantation embryos degraded the substrate following a short 'pulse-chase' period, resulting in markedly reduced fluorescence compared to ASMKO embryos, which retained the fluorescent substrate. Thus, the two embryo types could be easily distinguished by fluorescent microscopy. The fluorescent sphingomyelin was not toxic to the embryos, and the entire procedure could be accomplished within 48 h without embryo biopsy. We suggest that PED may be useful for the preimplantation diagnosis of lysosomal storage disorders, and perhaps other enzymatic defects where similar in situ assay methods are available.
UR - http://www.scopus.com/inward/record.url?scp=13844267415&partnerID=8YFLogxK
U2 - 10.1007/s10545-005-4418-7
DO - 10.1007/s10545-005-4418-7
M3 - Article
C2 - 15702401
AN - SCOPUS:13844267415
SN - 0141-8955
VL - 28
SP - 1
EP - 12
JO - Journal of Inherited Metabolic Disease
JF - Journal of Inherited Metabolic Disease
IS - 1
ER -