Is DNA test accurate? If she's my half sister then the dna would be 50%?

[Anonymous]

there's a rumor that my sister older than me is not my full sister her father is different than ours. I Have 6 siblings so we are all 7. Im the 6th daughter and the 5th (Jenna) is unknown if she's our really sister. Rumor back then that my mom cheated on my dad and my aunts know it and some people in our town that my sister is only half and my 4th sister (Abigail) told me that rumor and someone has told her about that and now Im questioning it too because she looks different than us but her surname is like us. My sister Abigail said our own mother and Jenna knows that she's not our fathers daughter but just kept silent. Now I know why she looks so different even her kids doesn't look like my fathers side.


I changed the name by the way for privacy***

[slatyb]

More or less. She will have none of your father's genes. Generic testing can tell whether she is your full or half sister.

[Anonymous]

95% or more, yes.

[Asker]

Even if she's my half sister the result would be 95% still?

[shortster]

Assuming it doesn't get contaminated or mixed up.

[Asker]

How does it get contaminated? Or mixed up?

[shortster]

Contamination can be the result of improper handling of samples and not properly cleaning equipment after each use. Samples can get mixed up with other samples if the operator mislabels a sample or enters results from the wrong sample.

[jahaims]

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