Embryo genome profiling by single-cell sequencing for successful preimplantation genetic diagnosis in a family harboring COL4A1 c.1537G>A; p.G513S mutation.
BACKGROUND
Genetic profiling of embryos (also known as preimplantation genetic diagnosis) before implantation has dramatically enhanced the success quotient ofin vitrofertilization (IVF) in recent times. The technology helps in avoiding selective pregnancy termination since the baby is likely to be free of the disease under consideration.


OBJECTIVE
Screening of embryos free from c.1537G>A; p.G513S mutation within the COL4A1 gene for which the father was known in before be in heterozygous condition.


METHODS
Processing of trophectoderm biopsies was done from twelve embryos for c.1537G>A; p.G513S mutation within the COL4A1 gene. DNA extracted from isolated cells were subjected to whole genome amplification using an isothermal amplification and strand displacement technology. Oligonucleotide primers bracketing the mutation were synthesized and used to amplify 162 base pairs (bp) polymerase chain reaction amplicons originating from each embryo which were subsequently sequenced to detect the presence or absence of the single base polymorphism.


RESULTS
Three out of 12 embryos interrogated in this study were found to be normal while 9 were found to harbor the mutation in heterozygous condition. Implantation of one of the normal embryos following by chorionic villus sampling at 11thweek of pregnancy indicated that the baby was free from c.1537G>A; p.G513S mutation within the COL4A1 gene.


CONCLUSIONS
Single-cell sequencing is a helpful tool for preimplantation embryo profiling. This is the first report from India describing the birth of a normal child through IVF procedure where a potential pathogenic COL4A1 allele was avoided using this technology.
Department of IVF, Akanksha Hospital and Research Institute, Near Shrushti English Medium School, Lambhvel-387310, Anand, Gujarat, India.
Nayana H
NH
Patel
Department of IVF, Akanksha Hospital and Research Institute, Near Shrushti English Medium School, Lambhvel-387310, Anand, Gujarat, India.
Harsha K
HK
Bhadarka
Department of IVF, Akanksha Hospital and Research Institute, Near Shrushti English Medium School, Lambhvel-387310, Anand, Gujarat, India.
Kruti B
KB
Patel
SN Gene Lab, Floor, A, Above Kansaar Hotel, President Plaza, Ring Rd, Aveerbhav Society 1, Nanpura, Surat, Gujarat, India.
Salil N
SN
Vaniawala
SN Gene Lab, Floor, A, Above Kansaar Hotel, President Plaza, Ring Rd, Aveerbhav Society 1, Nanpura, Surat, Gujarat, India.
Arpan
A
Acharya
SN Gene Lab, Floor, A, Above Kansaar Hotel, President Plaza, Ring Rd, Aveerbhav Society 1, Nanpura, Surat, Gujarat, India.
Pratap N
PN
Mukhopadhyaya
Department of IVF, Akanksha Hospital and Research Institute, Near Shrushti English Medium School, Lambhvel-387310, Anand, Gujarat, India.
Nilofar R
NR
Sodagar
COL4A1; embryo; in vitro fertilization; single cell sequencing; surrogate