Apparently there are several variations of the verse from John 1:18, but the main difference between the different renderings is the μονογενὴς θεός (monogenes theos, "the only God") versus ὁ μονογενὴς υἱός (ho monogenes huios, "the only son") part.
If we assumed for a moment that the variation with 'theos' is the right one, and monogenes means one of a kind, only or unique, the Greek says: θεὸν οὐδεὶς ἑώρακεν πώποτε· μονογενὴς θεὸς ὁ ὢν εἰς τὸν κόλπον τοῦ πατρὸς ἐκεῖνος ἐξηγήσατο.
Word-by-word translation without punctuation would be something like: god no one has seen at anytime a unique god the [one] being in the bosom of the father he has made known
What I'd like to know is if this sentence can't be (grammatically restructured or be framed in a different way and) read something like this (with a change in punctuation, and from the idea that monogenes means one of a kind, only or unique): “No one has ever seen God; the only (one) God. The one (being) in the bosom of the Father (OR sitting at his Fathers side) he has made Him known.”
And if we would assume that huios is the right one: “No one has ever seen God. The only son; the one (being) in the bosom of the Father (OR sitting at his Fathers side), he has made Him known.”
Note: I'm not asking if these are options theologically, but if they could be grammatically if you look at the original Greek texts and consider that they don't contain any real punctuation marks.